SN is to the left.
Silver 1
9/21, taking the armor/mr based on lane opponent and enemy team comp (if against a physical, armor, if heavy physical enemies, maybe take the crit one also)
Some AD/armor pen for lane, pref either 5% flat cdr + 5% from masteries or 15% scaling. Others just use whatever runes.
Average build, Titanic Hydra, Black Cleaver, Sterak's Gage, Banshees Veil, Randuins Omen/Deadman's Plate, Mercury Treads/Ninja Tabi/Boots of Swiftness. Sterak's can be replaced with another defensive item, and Banshees can be replaced with Spirit Visage if going 5% flat cdr from runes + masteries. Deadmans is a more offensive tanky item while Randuins is defensive. Boots are whatever you think is best in the situation.
Black Cleaver is mandatory. It gives him massive cdr (needed), lots of armor reduction (helps adc and any other ad on your team), and some damage and tankiness. Titanic Hydra is better than Ravenous to me, as it has higher damage, tankiness, and makes his other health items provide more damage (and thus be even better). While Ravenous Hydra does have lifesteal and more flat AD, that's not very useful in fights because Renekton is using his spells for a lot of his damage and won't be lifestealing much.
Titanic Hydra is a rush: Tiamat makes your W less painful to use (though it isn't very painful after that change a while ago) and Titanic is massive damage in the active. Black Cleaver same: get it whenever, provides cdr you want and great all around utility and damage. Sterak's is an amazing item, as it provides 25-51 damage from the base AD, a 30% max hp shield (huge!), and a size increase (opponents want to focus a huge thing more, and with this + R you'll body block almost all skillshots). Banshees is better than Spirit Visage most of the time, but if going 10% flat cdr or there is a Soraka it can be better. Randuins/Deadman is a needed armor item split in a more defensive or offensive choice. Boots, pick whatever suits the situation best.