I get ingrown hairs something fierce. For me the only solution was to stop shaving. I've worn a beard for about forty years. I shave the spots where it doesn't grow well about once a week, way under my chin, etc., and I still get an ingrown hair there fairly often.
So if ingrown hairs bother you, stop shaving. There's no excuse for shaving anyway. A lot of women have told me they'd rather snuggle up to a fuzzy beard than a face full of prickly stubble. It's a shame they don't make the connection that the prickly stubble they have from shaving their, er...., well, you know, is just as uncomfortable for us.
Men who criticize women in other countries for not shaving should be sent to Antarctica!