How to make a list of potential graduate school?
It sounds like you already have 1) a list of potential schools and 2) some idea what schools you can realistically get into and which you cannot.

So take these schools and split them into three groups: those you should be able to get into (safety schools), those for which you have a 50-50 chance, and those which you would be delighted to get into (like Berkeley and CMU). It doesn't have to be a very scientific split; a rough one based on your intuition or whatever it was that made you think Berkeley and CMU are beyond you suffices. Then apply to some schools from all three groups.