You can find the general interviewer's appraisal form (1131/5) at:
https://rq.cnrc.navy.mil/directives/forms.htm
This site has all the forms required to submit for OCS and more.
I did learn from my attempt that you should have a copy of all the information available on you to present to the CO (application, reesume, evals, other recommendation letters if allowed, PRT scores, etc) as well as several drafts of a pre-written recommendation letter. This goes for any officer you are requesting a recommendation from.
It was emphasized to me from several officers that these pre-written letters are good because the recommending officer can simply make a few specific changes and sign them, and they will not have to write something from scratch. It helps you because the letter you get shouldn't be lack-luster if you pre-wrote it. Don't be modest when you wrtie these, I was advised. The CO will change any flamboyant language they do not agree with.
Although the wonderful officers on here can certainly speak more to this point.
Hope this helps a little.