If you have an estimate, you can always submit and say “will file” and update it once you file. It only takes about 10 minutes to do the whole FAFSA.
I’m also waiting to get all my W-2’s and my 1098-T form. I graduated this past May and am working now, so I’m filing as an independent for the first time and had to do quite a bit of research and get quite a bit of advice. Do you have any specific questions?