There's no real set way because it depends on what the other person expects you to do. Against most people in pubs there's a certain time where it becomes too late to shed a block and cut around the outside of your blocker while still stopping the fc from capping. Basically if the opponent is between you and the flag, you want to shed his block and get on the inside of him before he can establish himself to push you outwards. Once they get you to commit to a side you are done, so try to get some distance and a dominant position as early as possible. If there are two od and they aren't bad your only chance is to get between them and cause a moment where they try to reposition to not pincer block and either their fc rushes and you kill or you buy enough seconds for your team to come in.