The beard on my face is kinda patchy. There are big patches of bald skin all around the chin area. Is there a tip to "activate" hair growth on the skin? I heard that using cognac on the area helps. Any advise I could get here?

Hair growth - how much, how fast, how thick, what color, where it comes in - is all genetics. There is no way I know of to make facial hair grow any differently. You're born with what ya got.

Check that - you can dye your beard if you don't like the color.

I thought cognac put hair on your chest?

put the cognac in a glass and drink it. or hey, just tip the bottle directly.... it won't grow hair anywhere, but it just might make you feel a little better about it all.