This is a guide that I have just began to work on, and therefore it will be a long time before this guide is actually finished. Twisted fate is a champion that is not only very flexible, but also absolutely one of the most useful champions to have on a team. The only other champions that can practically kill anyone, that got away at low health, are karthus gangplank, and ezreal. And ashe. In this guide, I will show you all the tips and tricks on how to play an atrocious attack speed twisted fate.

Albeit my skill sequence seems a little, random. There's a reason that I do it this way. Your pick a card is actually the ability that is the reason why Twisted fate is so strong. He has three abilities built into one. He can either do about 100+ damage on his next attack, slow you and do an AoE on his next attack, or get a good 2 second stun off on you.
I choose to get pick a card first because you want to be able to do something to a champion such as vayne who'll tumble into you, attack you once, then just walk off taking little to no damage.
By taking pick a card, you'll be able to get a stun off and deal just as much damage back to her. Next, you want your wild cards. You want to get wild cards up to level 2 or even 3 early game for some of the best harassment, ever. Wild cards has the longest range non-global non-ultimate ability in game. It also doesn't deal less damage with every subsequent target it hits, unlike sivir's boomerang blade or orianna's command: attack.
This makes it the reason why you want to get it up to level 2 or 3 early game, where it would do enough damage to make them be a little more wary of you.
Next, stacked deck is a very important skill for twisted fate.
Stacked deck not only gives every 4th attack a massive damage boost, but it also gives you reduced cdr, and increased attack speed. This skill you will want to max out after you max out pick a card.
Now, about destiny.
That skill can have its own entire section :3.

Many people can agree that this ability is one of the, if not the, most overpowered ability in game. It allows you to not only see every enemy champion, but also to be able to gate absolutely anywhere on the map. It can be used for ganks, finishing off people that got away, seeing if they're at dragon/baron, finding their jungler to kill, etc... I don't actually level this ability past 2 until level 18, because you honestly won't use it that often. You only want to use it when you can assure yourself the kill on someone, or even 2 people, or when they're all missing and you think that they may be grabbing dragon/baron to tell your team about it. Or, and this is on a very rare occasion, you can use it to gate out of a very bad situation. Because your gate isn't cancelled by taking damage, you can use it to get out of some situations at little to no health. Don't try to do this too much though, because you would be wasting the primary ability of destiny, which is to be able to see all of them wherever they are.

I use flash and exhaust for the summoner spells for a few reasons.
Flash is obviously a must for twisted fate for the ganks when your ultimate is down and for getting out of a bad situation.
I use exhaust because it seems that usually, people will get away with very little health left. Exhaust can assure you the kill.

Sometimes I may use ghost instead of flash for getting away and for chasing down the enemies when necessary.
I rarely use ignite, because if you need help assuring the kill, you should much rather use exhaust whereas that can also reduce the damage they deal to yourself and your teammates.

Clarity/Heal
No.

Rally/Fortify/Revive.
No.

Cleanse.
No.

Teleport is commonly used on twisted fate for more mobility around the map.
How much more mobility do you need?!

Clairvoyance.
Why? You can see where they all are with your ultimate...

Twisted fate is supposedly quite challenging. I'll explain how to play him and how NOT to play him.
Pick a card goes through a little loop for which cards it goes through. What card it starts at is random, and say if it starts at blue, it'll go to red, then gold, then blue, etc...
You want to harass with your wild cards, as much as possible. This is how you will get them to outstep their boundaries and get the kill.
Constantly be using your blue card to last hit the creeps. This will just give you more mana.
Another fun way to harass is to grab red card, and hit the creeps nearby to them. Will still deal quite a fair amount of damage, and will slow them.
Something I usually do is make sure stacked deck is ready for the next attack, grab blue card, and just hit them for around 250 damage. Then continue farming creeps, rinse, repeat.
Then, when they begin to outstep their boundaries, grab gold card, make sure stacked deck is ready, and go rape.

Will be finished at a later time.