The first Kayle is the Omni one, which can go any which way and also my 0cs to carry item build. I've struggled alot with finding a build for Kayle, probably like you, and I've tried them all (probably like you're doing), AP, Hybrid, On Hit/shred, AD/AS, tank, jungle, 0cs support. I even would break down the numbers on damage output of each. One of the problems I've run into is that every build has it's uses and good points and it's hard to go with one. With an AP build your Q hits like a truck and you can heal better. You can rip people up an AD and Shred builds. Has one of the fastest jungle clears while jungling. Can sustain and harrass really well as a support (just don't have Soraka like heal expectation, just sustaining). This is one of Kayle's greatest and most over looked strengths. It's also frustrating as hell. So after hundreds of games, tweaking and experimenting, trying new things, I came to this, my Omni build. By that, I mean, it can go everywhich way depending what your team needs as the game progresses. Up against a lot of tanks? shred them. No AP on your team? fill the role. Etc. Granted this mostly works in solo queue. If you have a team and you're deciding on your team comp you should be able to choose someone better than Kayle...unless you're looking for a really adaptable jack of all trades...say you already have an AP,AD,Tank, Support, and Jungle. Other champs can fill multiple roles too, KAyles just one of the best at it.

Okay, I don't want you buying a **** ton of different runes and expecting you to switch them, so red AS, yellow mp regen, blue CDR, and MS quints. Why? well, Kayle has really good synergy with AS. Has alot of mp issues in early levels, CDR helps keep your E up and brings your R in a lot more, and MS because Kayle needs to be able to keep up with opponents or run away depending on the situation. If you're going to switch one out I'd probably recommend the CDS or Quints. AS is too good, and the mp probables too annoying.

Okay, in the offensive mastery I put just enough to get both penetration masteries. Why only 1 point in AP? it had to go somewhere and honestly Kayle doesn't scale off of AP well enough to put more unless you're going full AP...in which case you're only mising 3 AP. In defensive I put 3 points into armor because it will help you jungle and because you're most likely going to be laning against an AD champ if you're top or bot. And then the rest in support for summoners, the speed bonus, and gold bonus in case you're stuck support....but really, gold is always useful.

Okay, unless you know you're going to be jungling, start with boots, 2 pots, and a ward. Why? because honestly you're going for a kill by lvl 2, you need the boots. The pots are just for sustain. Kayle has one of the strongest lvl 2s in the game, which is great, too bad it doesn't last. Anyway, seems like a waste not to capitalize on that. So unless you're a jungler, regardless of role and with a point in E and then a point in Q, you should be able to force a retreat or get a kill/assist. After this you're going to have to make a choice. And there is an extra decision if you're bot, you have to decide if your carry is okay and worth supporting, or if you're going full AD carry too and take all the cs. If you decide to support, you still have carry potential later, but it will be a long wait with a ****py carry....really long. So support if you've decided your carry is good, and AD if he sucks or there is another support/tank in the lane, or one of the other 2 lanes or jungle. So up top of this guild, Kayle number 1 is my 0cs suppport, items focus on GP/5 items at first and slowly switch you to carry, you can finish off the GP/5 items and still have quite a bit of success, I do that when the game is almost over and I have no hope and finishing my build. Kayle 2 is AP (to be honest I rarely do AP Kayle, only when my team decided to go all AD do I do that, I just find AD to be so much more damaging). Kayle 3 is AD and is pretty straight forwad AD. Kayle 4 is jungle, and pretty much switches to AD. Kayle 5 is shredding/on hit for when you find out you're facing a tank or two in your lane (sometimes I replace the bloodrazor with a PD, and sometimes I replace Malady with Wit's end, depends what you're up against). Buy pots/wards as needed with all builds. I usually carry pots on me until mid game at least.

okay, skills change depending on your role. lvl 1 always E, no exceptions. Lvl 2 always Q unless you're jungle and need the sustain. Then if you've decided to support at lvl 3 W, if you're going AD E again. This is how I do it.

Support:
E>Q>W>W>W>R>E>W>E>W>R>E>E>Q>Q>R>Q>Q
AD:
E>Q>E>W>E>R>E>Q>E>Q>R>Q>Q>W>W>R>W>W
AP:
E>Q>Q>W>Q>R>Q>W>Q>W>R>W>W>E>E>R>E>E
Jungle:
E>W>Q>E>E>R>E>Q>E>Q>R>Q>Q>W>W>R>W>W

I usually do the AD or Jungler sequence if I'm solo top, depends how you're doing at lvl 2.

The goal here is Omni and adaptable, so sadly no smite for the jungler, which sucks if you're stuck in the jungle. Basically keep the summoners applicable to every role. I go teleport and flash. Great escape/position in flash, and teleport is a quick heal/buy/save/gank another lane button. Those two will always be useful no matter which role your in. Smite is great for jungle, ignite great for AD and shred, and clairvoiance great for supports, but you might not be in that role.

Pros:
You can fulfill every role.
Decent dps, especially with AD kayle.
A support that can turn into an AD carry late game and still have a decent kill count.
3 sec of invulnability.
Sustain.
Ranged AOE auto attack.
Slow and speed.
Longest range heal (not counting Soraka ulti).
Cool Angel character.

Cons:
You aren't the best choice for every role, others will outshine.
Squishy.
Really bad rep, people will hate you just for choosing Kayle. Even though statistically she's actually decent.
Mana issues.
Not always ranged.
Heal is lack luster.

For jungling, you're going to need a leash, you don't have the masteries or smite. You can do it without but it's painfully slow and near useless. So if your team wants you to jungle, then start with blue, go wolves, wraiths, red, gank, or golems. You should be fine after that. Give up buffs to those that can use them better when they can use them better. Be sure to gank and watch out for the enemy jungle, the good part about not having smite is until you gank they probably won't know you're jungling.

When farming as top, mid, or AD carry, in lane try to just last hit, with E you're going to push your lane, so watch for ganks. And push hard right before you go back to buy.

As a support, farm every time the carry is not in lane or can't get to the creep in time. Oh, and go for kills, if the carry can get the kill with absolute certainty or steal it off you, that's fine, don't get pissed, it's a good thing and will help your team win, but don't risk letting a kill go hoping the carry will catch them.

In a team fight careful use of your ulti will make a big difference, if you can save someone as the team unloads on them you might have just won the team fight. saving someone after they've been beaten and running is awesome, but it's a poor second prize. Remember that if you've gone AD carry that you're ulting yourself most of the time so you can last longer as you dish it out, this is great if you're going toe to toe with their carry, careful timing of your ult can turn the tide.

Kayle is so versatile, it's important to know where and when you should take on different roles. In one of my recent games I was playing 0cs and ended up laning with Leona, I was going to swtich to AD, but we ended in a lane against two tanks...I went shred, it worked out fine. In another game I was laning with a really..."cautious"...caitlin, who'd run away all the time instead of engaging. So I went AD and took all the cs, and ended up carrying. So again, everything is situational, but you're one of the most adaptable champs in the game, so you're good. You could even go tank, Kayle has one of the highest base healths, and it's easy to build on that.