To my knowledge you don't get banned/restricted for dodging a game, only for leaving/afking IN the game. If it's champ select you can close the game before it locks in and starts to load (so like right after last pick locks in at the latest just to be safe), or if you're a lower pick and people are already raging at each other or troll picking, just don't select a champion.
You'll have a time delay where you can't que up for a few minutes (a whole lot of minutes if you dodge more often back to back or maybe even same day, not sure), but that's to prevent people trolling by que dodging then joining again and dodging again to keep people from getting in game. That delay isn't the same as a report or anything.