Another Transfer Qyestion

[Everyyeardisney]

I have never transfered points before and i have a few questions. I am planning a larger family trip and need to transfer some points from another member into my BIL's account. My BIL is hesitant about giving out his DVC information out to anyone else. Does anyone know what information he will need to give the other member so that they are able to transfer points into his account. Please if possible walk me through the process he is a newbie!!!!
Thank you so much

Thanks again,
Nicole, mom to