how to get fuller cheeks

Well first of all I'm not a sir and neither are most people who post here, but that doesn't mean we can't help! :) Have you heard of facial yoga? Some people swear by that and though there's no solid scientific evidence that it will do you any good, there is no reason not to try either. The worst that can happen is losing a little time.

Hydrating your skin well, with a deep moisturizer such as hyaluronic acid, is also going to puff your cheeks out if sunken cheeks are caused by something like dehydration on a skin deep level. However, if the cause is that you are underweight, then only putting some weight on will help you.

can masturbation be the reason for sunken cheeks

it can be

how much days gap should be there for masturbation to nullify its harmful effect

Facial yoga and balloon blowing will help you to get chubby cheeks. I have read it in an article but did not try it. Or else there are many cosmetic procedures like cheek augmentation, fillers, etc. to make your cheek chubby   

What can I do to have big cheeks? I have just lost my weight due to a little illness, so I need a rapid recovery, especially "BIG CHEEKS" first.