Applying for aid with the Federal Application For Student Aid is actually pretty simple, especially if you do it online. The official FAFSA website outlines the main steps for doing so - Ill paraphrase them here:

1. Complete the FAFSA online (it can be found by clicking here) and provide the signatures required.
2. Wait for the FAFSA to be processed. Once it is, you’ll receive a Student Aid Report. On the FAFSA website, they’ll refer to this as your SAR.
3. Check out the Student Aid Report for accuracy. This is important - clerical errors happen all the time, and can be a huge hassle to clean up later on!
4. Keep a printed copy of your Student Aid Report - Again, this is important. Keeping good records of everything related to your student loans will save you time and effort later on.
5. An Expected Family Contribution should be printed at the top right of the page. (What is EFC?) Your school will use this number to award your financial aid.

Just like that, you’re done! Find more information on the official FAFSA website.