There are a number of ways. I personally use a mix of the github site tools for creating repos and doing pull requests and merges; command line stuff on my local machine for creating, committing, and pushing branches; and occasionally some features in my code editor to do a few simple things like reverting a file back to its latest version when I change my mind. Probably the most basic intro to using the GitHub site: https://guides.github.com/activities/hello-world/
