All what we have to do is to farm up. Don't go in early unless you have 100% to kill enemy. Just wait for late game and crush them will full power. With zhonia and shield that reaches 1000HP u are bassicly unkillabe, with good support like lulu or jungler like zac you have very easy game in late game. All what you need is to kite enemy tanks and assasins and farm a lot. Try getting easy kills with W+R+Q on low healt targets or just use ur r on low hp enemies to get some kills. Play agressive and show domination on mid game. Try getting every objective. With 1 or 2 mountain drakes u have easy baron at 20 minutes with guinsoo.