When I have to make a series of pull requests that stack on top of each other (i.e., each subsequent commit is independent on the previous one), I just work on each one in serial and then push the commits.
I also often work with situations where the commits are non-related, and in this situation, I wonder what the proper etiquette should be. What I have been doing is essentially working on one commit, pushing it, then resetting my local branch to the remote master branch before working on the second commit, and so on. Is this the recommended route when the commits aren't related to one another?