I submitted my resume along with my application, because I couldn't express everything within my essay and extra-curricular listing section. But it is ultimately up to you to decide whether to do it or not. In my opinion, if you have your resume on your laptop/computer right now, you might as well as just submit it.
In terms of formatting, there isn't any specific format that you need to follow. Just make sure that it isn't too complicated (and it should be clear!). Also, in my case, I avoided using any generic resume format (especially ones on the internet) and decided to make my own since it would be much easier to manage/update.
P.S. I submitted the app with Early Action so I remember doing this...
Good luck!
