I will give you one tip, and it's the only one I have.
BE CONFIDENT.
All these 'tips' mean NOTHING if you do not walk out feeling your best self, I break all of these rules, I have grey hair, really grey hair, I LOVE IT, I have embraced it, looking old? fuck that! This is me, I put it up in a massive grey quiff every day. Nails? Fuck that, the only person that ever notices your nails is the person whose cock you're grabbing and by that point they don't care.
Eyebrows? Have some, that is all, good to have eyes too, doesn't matter what colour they are or how they are defined, can they see? FUCKING BRILLIANT. Look at the world with them.
Legs? Do your legs stride? Marvellous, let them stride, let them be strong, DON'T SLOUCH, you've nothing to be ashamed of, swing it baby.
Teeth? Do you have some? Do they work? AMAZING, so they're a bit crooked or yellow, SMILE, who gives a fuck.
SPEAK, do you have something to say? We all do, say it, don't mumble, say what you have to say. SPEAK.
We are all effortlessly human, (with a little effort), don't ever be humbled by others to not be yourself.
Really.