door hinge kit... colour?

just got a new door hinge kit and was woundering what is the best way to paint and prime?

I made a mistake and only painted the outside .... Oops rust trails with a week.... Just removed em all, wire wheeled to bare metal, dipped in kurust n allowed to dry, primed front n back with high build and finished with a gloss black topcoat front and back, then mounted with lots of copper slip.... That better not show rust again lol

Oh and used stainless fixings....

I used electrolysis because I wanted to get the holes clean inside and they are hard to do by hand. Plastic bucket from Asda etc and Soda, battery charger and leave for a day or two. And hey presto. +1 for stainless fittings.

ELECTROLYTIC RUST REMOVAL (ELECTROLYSIS)