I am thinking of painting some of my Genrations/Classics/RTS transformers & was wondering the best way to do so?

I know there are people on here who do a bit of painting so I wanted to see some advice before proceeding. I am not looking to paint huge areas of the figures just add highlights Hasbro should have in the first place. Just details to the grills, exhaust, wheels & lights & maybe some of the robot parts.

I have a spare RTS Jazz to be my test victim & he seems happy enough to be painted as he said he was "too whiiiiite my man! I need some colour apps baby"

I have heard the Tamiya hobby paints are OK & was thinking of using a fine brush to paint it.

Thoughts?