Best Way to Collaborate on a Project

I am trying to post my current game up on GitHub. The problem I am currently having is that files over 100 MB aren’t allowed. So some of my game assets aren’t able to put up on GitHub.

Not to mentions there could still be problem with referencing. Last time I tried to simply copy and paste my assets into my project. There were a ton of referencing issues since I didn’t use the game import/export tool

I am curious how other people are doing it. My team is spread out so physically getting together isn’t an option.
thanks for the help!

GitHub, BitBucket or anything of that nature. This link explains everything perfectly:

https://answers.unrealengine.com/questions/16787/how-to-setup-git-for-an-ue4-project.html