Re: mehndi day grooming??
It's a personal choice of course and insha'Allah i'm gonna wear makeup on my mehndi. The trick is to stay away from dark colors. But even if u go with darker colors...who cares!? It's YOUR mehndi and u have every right to look ur best!!
You have the rest of ur life to look "simple" and u only have a mehendi day once (hopefully!) and it'll last forever in ur pix. And just cuz u look good on ur mehndi doesn't take away the "shine" from ur face on the wedding day. They're completely different looks.