How to report people?

like, not after a game, but any time? you see, I was in draft mode and some guy was support, he said he couldn't support: I was ryze at the time and decided to tell him that ill support, he proceeds to ban ryze and tell me that he'll continue to support..., i thought I had chosen nami but didn't realize the other team had chosen nami, but when I only had a few seconds left, I tried typing in soraka, but it seems that the chat in draft mode for me is super laggy, causing me to fail to lock in giving me a penalty, if you would like a name just ask.