Renekton is a AD melee carry. Unlike many other AD melee carries he is natural a aggressive champion and a fighter because of the benefits fury gives him for attacking/cull of the meek. Also in conjunction with his other moves, a full move rotation typically leaves you with decent health, your enemies injured, and you still farming.

This is not a typically guide leading people step by step on how to play Renekton because I find that any guide that says "Build this way always" would be inefficient for explaining the depth and utility of this champion. I 9/10 times while playing Renekton get these items of because they are all great items that increase his damage output/ farming/ and survivability and synchronize with Renektons spell mechanics very well.

Throughout my guide you'll see me referring to Renektons 'full rotation' which is simply as follows:

1) Slice into a group of mobs with 1 or 2 hero's (only do this if if no more than one of them has a stun)
2) If you are within melee reach of a champion immediately after slicing (if not then skip to step 3) into a group of mobs you cast your Ruthless Predator and auto attack them while they are stunned
3) Cull the meek ESPECIALLY if you have your 50 fury (ALWAYS try to at least barely hit as many units PLUS a enemy champion with this because it will give you a decent amount of health back especially at higher levels)
4) Dice out of the group into safety

You should ALWAYS be able to do this unless both of your enemies have stuns (Scion & Taric is a great counter to Renekton)

Honestly when it comes down to it, the reason that you are going to better than anyone else as Renekton (Regardless of what champion they play) is because:

A) Being more intellectually aggressive with Renekton will benefit with you hurting the enemy and you healing yourself
B) You will be inadvertently killing mobs when you are slicing and dicing and culling the meek in the middle of large groups, also you will be gaining more rage, and if you have the dodge runes and masteries set up correctly you will have a dodge speed buff increase on you after diving into the group of mobs, and if someone decideds that they need to run because of low health you will have the speed advantage.

Some other things:

Becuase you can get 35% CDR with Golem Buff and Blue Elixir I do not suggest to get ANY CDR items on Renekton, and if you do it should only be Yomuu's Ghostblade because of the armor pen, attack speed, and movement speed buff from it. Otherwise anything else is a complete waste.

Renekton benefits from being more tanky (With Sunfire Cape and Trinity Force) because he's all about doing a bunch of AD damage in a small area. Try to focus on being a hit and run character unless you have popped your ult.

*THE HARD PART*

There are only two real things that I consider hard about Renekton:
1) Deciding when or when not to tower dive a champion (It may seem like a great opportunity but imaging if someone stuns you AND you can't dice out of range of the tower, YOUR SCREWED!)

2) Deciding when to use your ult. This is a tough one because you can use it to trick people into attempting to dive you, but also you probably wont use the full extent of your AoE damage this way. OR you can pop it and put yourself in the middle of a team fight and hope that they all don't think 'Oh wow, this Renekton is doing AoE damage from his Ult, from Sunfire Cape, and Cull the Meek and Slice and Dice, and we should probably do something about that' because if they do and decided to focus you, you WILL die.

Renekton NEEDS his speed and maneuverability to be able to get in and out of good and bad situations fast, dealing all of his damage in bursts all the while healing himself.

As you'll notice I only have four items as part of this guide, and for a good reason. Because with any game not every enemy team will be the same I find that you will not always build Renekton the same way (if you're good). But, the four item I show are pretty much a necessity to playing a GOOD Renekton for 'MOST' situations.

Rather than choosing the Ionian Boots of Lucidity I typically get Boots of Swiftness as either my first full combination item or second, depending on if I can get Sunfire Cape first or not, which I typically will not. But anyways the reason for this is because Boots of Swiftness will help you chase someone down, tower dive and stay alive, or get away just by that tiny iota of a distance between you and your 'certain' death. Also when and if you are not able to Dice out of a battle this will help you get out as quickly as possible if a team fight turns sour.

For the Sunfire Cape and Trinity Force they both increase your survivability and damage, and more specifically the cape increases your farm rate by a huge amount. Also the reason we like Trinity force so much is because of your ability to get Phage at lower levels to increase your HP if you're taking a lot of damage, and/or sheen for a HUGE increase in Renektons melee damage output. Getting sheen is SO important I cannot stress this more, despite the fact that it is a mana and ability power item. But, the reason being, because Renekton is a 'dive in, do damage, dive out' champion, with every one of those cooldowns if he attacks with the sheen proc up he does a SIGNIFICANT amount of damage, more so than a Renekton without a sheen.

Pros:
Great burst damage
Great escape capability
Great laning survivability

Cons:
Bad team fight survivability
Renekton will be a target if the team isn't stupid

I cannot express to anyone playing Renekton the benefits of getting the level advantage more than any other part of this guide to this champion. (Not even the items)

Renekton is an AMAZING solo laner, and a AMAZING 2v1, especially with dodge runes, because of the way his slice and dice works. The ONLY time you would need to worry is if it was 2v1 with 2 people who have some sort of significant disable, and still you can play defensively till you hit 6 and wait for someone to make the wrong move and get that advantage to get ahead.

Because Renekton needs no mana, and his cooldowns get shorter as his skills level up he is a great farmer. Once you get Sunfire Cape (and especially if you get it early) you WILL out farm everyone, including other solo laners on your team or against you, and you need to make sure you farm this much because it is so simple with Renekton.

If you follow the general tips that I give in this guide (try to get a understanding of how Renekton works from this more than anything) you will excel at him and you WILL do good because he is a reliable hero.

(This is my first guide, and I'm pretty tired but here goes nothing!)