I'm 27 and have been "out" for several years. Prior to having "the BIG conversation" with my parents and family, I was already wearing girl clothes and make-up 80% of the time... so it wasn't a huge shocker what I had to tell them. Pretty much I was dressed as a girl 100% of the time at home and weekends.
Finding a good therapist experienced in MTF/FTM gender issues is key. You might consider meeting with one prior to talking to your family.
I'd also recommend only doing what you feel comfortable with and what feels right and comfortable to you. No right or wrong here. It's not a race or competition either. I will say, that with practice (as with many things in life) comes perfection. So the more experience with makeup, clothes, picking out the perfect outfit, fixing your hair, and on and on, the better you become at it. Especially since the majority of us are several years behind cis-girls grew up dealing with these things everyday.