AP? DPS? There are all kinds of builds for TF, but from what I've found, a hybrid works beautifully for most of the game. Nearing the end of the game, since AP becomes less useful, the items gotten for TF will generally be shifted towards DPS.

IMO? AP has become LESS EFFECTIVE, since AP scaling has been shot down. I also don't think burst damage is the way to go with this champion... I would leave that to our "OP" Ryze :). DPS TF, on the other hand, is waaaay too inferior to Jax and Tristana. You will just get eaten by them with your pitiful hp. If you become the main DPS of your team, you will be focused, and will most likely die pretty easily.

I've read lots of TF guides, but when testing them out, many are unviable.
Yeah, I can say that. I actually do my homework. Math is my strong subject.
Math and practicality are two separate subjects, so I test out everything beforehand.

By the way, if you're looking for a kiddie guide with lots of colorful pictures, you're sorely mistaken.
Please find another guide to fulfill your childish needs. Recording videos is too much of a hassle, as well. To the rest of the men, MOVING ON.

*NOTE* Twisted Fate is a delicate character- bad early game spells GG.
TF's top priority is to spam gold cards on the enemy's carry. Damage comes second. This is why we'll be reducing cooldown to improve his stun capabilities. Do this right, and you'll be called "OP."

*haha. I bet everyone else here likes being called OP from the enemy team. It's ******ic.*

AP
+high burst damage
-low AP scaling
-after you've used up your skills, no significant damage for another 4-6 secs

DPS
+decent DPS...? lol
-inferior to true carries (Jax, Tristana, Ashe)

Our Hybrid:
+decent AP burst due to Guinsoo's
+damage output is pretty close to DPS, almost the same.
+burst damage is pretty close to pure AP from early to mid game.
-in a 1v1 fight with pure DPS TF, hybrid would likely lose.

Pros:
-Difficult to counter (since he's AP and AD)
-One of the top gankers
-Massive damage output
-2sec stun with 4-6sec cooldown (IMBA!)
-Extremely versatile character, capable of being a DPS and/or AP
-AKA Baron Stealer
-One of the best backdoorers (if not the best)
-Map control
-If you're bouncing around, opponents will feel your lane presence and get paranoid
-"Quick! Build MR! That TF is going AP!"
"****, never mind, he's going hybrid."

Cons:
-Squishy
-Hard to get used to
-can't get enough magic or armor penetration

As far as masteries go, it's certainly debatable where one would put their masteries.
I personally go with 9/0/21, though you're certainly allowed to think differently.

I use...
marks = armor penetration or magic penetration runes
seals = health per level
glyphs = flat or /level AP runes
quintessences = flat health

why health? TF is squishy, hands down. If you can get your hands on 3 greater quintessences of fortitude, it'll increase your health by ~100 at the very start, raising your health from 400 to 500. In early game, it makes a pretty damn good difference. Health per level will make sure you have extra health as the game goes on- by lvl 18, you'll have 175 extra health with 9 of tier 3 seals. Like Calys so stated, magic penetration would work pretty well in this build. Armor penetration is for last hitting and being able to do full damage on squishies. (Every hero starts out with base armor, armor penetration therefore is pretty nice. Creep and minions have armor too.)

Runes are debatable. Whether you disagree with this rune set or not, I don't care, go cry to your mom about it if you have a problem.

Flash - Works pretty damn well for most characters. For TF, it's invaluable.

Ignite or Exhaust as a second skill, depending on your playstyle.

ALTERNATIVES:

Teleport - More map control, but you have Destiny.

Clairvoyance - Meeehh... it's alright, but you should have one of your allies get it instead. You have friggin' Destiny.

Ghost - I could see how this would work.

Rally - NO

Revive - "Yeah, I agree no one should use this on TF either... WHAT." I know, it sounds crazy. When we first saw Pantheon with Revive, it sounded dumb, until we met one that actually used it really well. Yeah, this skill is viable on TF because if we happen to die in a teamfight, we can jump right back in the fight with Destiny. I normally wouldn't use this though, since I make it a priority not to die, but this is definitely a viable skill. You haven't seen anything until you've seen a Pantheon and a TF on the same team with revive; They can be everywhere at once, and they retain global presence.

Heal - Sure you can replace the second skill with Heal, but it's not really as useful on TF. Health pots would replace heal, in most cases. Heal on TF is just a waste.

Clarity - Mana pots, you fool. Otherwise, blue pill back to fountain and destiny-gank someone. Nashor's Tooth will take care of mana for spamming skills mid-late game.

Fortify or Smite - NO

Start: Sapphire Crystal + 2x Health Potion
OR Doran's Ring

CORE:
1. Sheen
2. Mercury's Treads or Boots of Swiftness
3. Guinsoo's Rageblade

4. Moving from 6sec to 4sec Pick A Card: Nashor's Tooth
(suggested for the pros with getting gold cards) (50% attacks speed! same ASPD as malady, but with better additions.)

This is where your item build should start following what happens in the game...

Optional:

-Turn Sheen into Lich Bane, only if your opponents aren't building much MR.

-against heavy nukers, Banshee's Veil would work nice,
Guardian Angel is also pretty nice at this point in game.

Build some DPS or

OK, if you get the general idea of TF's skills, you can skip this section.

Loaded Dice - Pretty self-explanatory; your team will love you just for being there.

Wild Cards - The damage on this thing is pretty spectacular from early to mid game, along with a godlike range. Some reasons not to be using this skill before its level 3: 1 This skill does insignificant damage before level 3. 2, It usually comes as a pretty big surprise the first time you use it at lvl 3. This skill is also considered a skillshot; aiming this well could net you a kill in the fog of war (haha I've done this once...)

Pick A Card - Blue, red, yellow, blue, red, yellow, blue, red, yellow. I hope you see a pattern. Practice and develop reflexes to pull the right card when under pressure, and it could net you a kill or save your life. This skill is invaluable to TF. Pull blue cards for some free damage, Red cards for AoE dmg+slow, and gold cards for stunning. During the laning phase, the red cards are pretty useful for their AoE damage. You wouldn't even need to hit the champions to deal damage to them. Most of the time, however, you're trying hard to pull gold cards. *NOTE: Blue cards will give back less mana than the cost you've used to throw it, until you have gotten a decent amount of AP.*

Stacked Deck - This skill is sexy, but the other skills are so important that we'd have to keep only one point in it. As your second skill, this can be used in conjunction with Pick A Card to deal some badass damage, which is why you must always keep an eye on your stacks of this skill. When running to gank someone, having that extra damage can be the difference between a kill and getting killed, so always keep this in mind.

Destiny - Your ultimate, and for a good reason too. Even though it's been nerfed, you're still very capable of destroying the other team with this skill. Be sure when you teleport to gank, that you pull a gold card first, and that you're behind and still fairly close to your target. Teleporting too far away, and they'll easily run away. If you're saving someone's butt, Pick A Card can be skipped until after you've teleported in. Because you can see every enemy with this skill, be sure to evaluate the situation before jumping on in. Is he going to die anyways? Am I going to die if I teleport in? If they're going to die anyways, the best thing you could do is to hope for the best; you might put yourself in a bad situation and die if you engage with them. Sad, but you're going to have to live with it. Don't forget that you can also use this skill to run away! Most people forget that.

You can start by casting your Pick A Card if you're ganking someone across the map and teleporting to them. MAKE SURE you got your gold card before even considering to gank. Teleport right behind them, but not too far away. You just want to be able to hit them with that gold card and stun them. Make them eat damage with your Wild Card, and throw a few extra hits at them. If you can chase them for another 6 seconds, do so, cause you can always use your combo and hopefully finish them off.

So to recap, the basic combo is:
Pick A Card > Wild Cards > HIT

As I will mention later Guinsoo's Rageblade will make your build shine. In half a second, pulling off the combo in half a second will rack you 3 stacks on Guinsoo's Rageblade which is equal to 12% increase in AS and +18 AP. When lvl 18 with Nashor's tooth, this combo can be repeated every 4 seconds. With higher AS, TF can easily do a ton of damage in a short amount of time. Be sure to cancel attack animation and step forward a little every time as to make sure that they don't get away without losing an autoattack.

Even with a high knowledge on TF, positioning, and overall gameplay, you cannot evade death all the time from higher ELO players. They will recognize you as a threat, and they will target you. There are a few notes to take when playing with stronger players:
-take hp items. I know in MOST games, even in high level games, hp items can be ignored, but if you start playing with a godly premade, you need to be able to be take more damage.
-don't waste destiny. Using destiny to push back a creep wave will signify to the opponents that you are vulnerable, desperate, and will not be able to cast it for another 90 seconds or so. By using up destiny, you use up an escape skill. One mistake like that in higher level games may lose you your game.
-sight wards. "Carries don't get wards!" Screw that. You may have destiny, but that's not enough. My motto is, "Map awareness is everything," and you should write it all over your body. If your team has teleport, you could all move to that ward in an instant for a nasty surprise for your opponents.
-know when to back off. E.G: Since Olaf came out, he's become the biggest threat to most ranged carries. He will activate ghost/youmu's blade and his ulti, and charge straight through your allies as if they were nothing. You can't go over him. You can't go under him. You can't go arou- ok. You can move around him and still stun his teammates while taking minimum damage from him.

Explanation:
Pick a card is chosen early for its 1sec stun; you know, for early first blood, escape FROM BEING first blood- it has plenty of uses even at level 1. Building on this skill early on,however, does not give results due to the 0.25sec increments. Wild Cards at lvl 1 and 2 don't do enough damage- that being said, don't start spamming it until you get to Wild Cards 3. Wild cards is top priority next to Destiny for its massive damage. Stacked deck makes last hitting easy; the extra 60 dmg (lvl 1) early on is awesome when harassing/killing opponents.

TF doesn't need lizard or golem buffs to pull off a gank, but it certainly would help. If no one on the other team needs the buffs, feel free to take it. I suppose I don't need to teach you how to kill the creeps.

"Your value can be summed up by the number of gold cards you pull during the actual team fight." You should write this all over your walls until people think you're crazy. Your team will be relying on your stuns a lot in a teamfight. That being said, never initiate; you're far too squishy. Instead, once your opponents are focused on your tank/initiator, stun their carry and engage. Your low cooldown on your Pick A Card can drastically decrease the effectiveness of the opposition. If they're going for your carry, die for him if it'll save him/her. For anyone else, it really depends on the situation. Personally, your importance is near that of a carry, so avoid being in the middle of the battle.

Twisted Fate can be a pretty "OP" character when played right. Teleporting behind someone, stun, and Wild Cards should be very effective in bringing down their hp. You should NOT be the main DPS in the group. If there is no other DPS in your group, consider choosing someone else.

Thanks for taking the time to read this guide,
leave some constructive feedback if you would like,
let me know if there's anything I could add, and how the build worked out for you!