Have you looked at the form? It's fairly straightforwards - I would hope someone capable of passing the CISSP exam could figure this out for themselves!
Basically, it's an online form where you enter relevant data in the various fields with a view to showing you have the correct amount of experience to qualify for the full CISSP certification as outlined in the link below, or otherwise you need to endorse as an Associate:
Once you open the actual form, select CISSP, select Associate or Member based on your current experience, if you opted for Member select you want ISC2 to endorse you (I'm basing this choice off your other thread), and then fill in your job history as per the form in the screenshot below. If you have multiple jobs that make up the experience then add each job that's relevant in its own job history form: