Unlock camera mode

Repeatedley use it. Until you get to that point, hold the center on champion button. (Space bar by default i think)

Start with unlocked in Aram, then on twisted treeline, and finally on Summoner Rift. I found it easiest to do because I moved up in map sizes gradually until I eventually didn't notice I was completely unlocked. It takes getting used too but once you do get it down, it makes things easier to play.