How to get a really good 6 pack for a girl?

I would like a 6 pack and I know there are so many ladies out there who have very pretty flat bellies so just wondering, how do you get them? I do yoga and pilates, an ab workout class about once or twice a week, i’m 123 lbs and 5’6 (i don’t know i’m overweight? haha feel free to correct me if i’m wrong though i don’t want to be classified as overweight and unhealthy!) i would look to have that super pretty line that people have in the middle of their abs.

also, i used to be super thin though just naturally but then i gained some weight as time went by so now my skin is all lose fatty and stuff. haha. is there anyway possible/any moves that i can use tighten that up?

same with my legs. except i do not want venus and serena legs. as amazing as those ladies are, i do not not believe i would admire their types of legs if i had them. haha.

haha and to those who have really pretty abs and legs– all power to you! it’s not an easy thing to accomplish!