So...... there are pretty much 2 differnt ways of playing this character. 1: you can play it as a pure support/tank character
2: an normal attack/support character
I personally like the support/tank character because sure you wont be racking up the kills but they still come. Trust me. Plus your team will be very greatful when you are poing 15+ assist games. The basic plan for this build is to just try and increase your health as much as possible in order to tank for your squishy team mates. Nuke mages (specially Ryze) work well with this because your being annoying and they are packing in the hits and when they try to flee like 110% of the people in this game will do you just use your gay rocket grab attack to seal the deal.
Items: Your 2 biggest items you will want to get is The guardian angel and the warmog's armor. remember your main tactic is to make it impossible for you to die and with the combination of mana shield it pretty much makes you indestrutible. This build wont allow you to 1v4 but it sure will help you enjoy the game more when your constantly making people rage quit because of rocket arm ;)