Need a few tips on painting. I'm not the best artist that's for sure!

I just trimmed my fenders and prepping for paint.
I want to do flat black about 1/2" around wheel wells but how do I make a clean half circle with tape? It always turns out looking like a hexagon so I keep ripping tape off and haven't painted yet.
Also I want to hit the lower 1/4 of the rockers. should sand it all the way down to metal or just scuff it up and paint over?

Everyone likes pis so here ya go.

 

Not pis... Pic's* Stupid phone!

 

Are you going to use bedliner? I don't think you'd have to be bare metal with that.
Nice jeep though! I love the green and black jeeps

 

No bed liner this time. I use it on my bumper and its just to hard to keep up with it. I'm gonna just rattle can primer and flat black that way it easy to fix small spots. Thanks!

 

I bedlined first of all but here is what I did.


Marked the area I wanted to paint and used a sanding disc on my grinder to get down to bare metal. The taped up more to avoid over spray. Then took my knife and lightly cut the tape to leave the same angle look as the fender well. Just don't dig it in the fender.

 

Yeah that sounds like my next step. I just didn't want a big old knife mark in between the factory paint and the black but like you said I will try to go light. Thanks for the tip. I will try again in the morning.