First of all, there has been many threads of this, so search. But i'll help you anyway.
To make your paint stick better, do a few coats of primer, then a few coats of MONTANA GOLD, or RUSTOLEUM. Then top it of with a couple coats of gloss.
And for the color of the deck, or head tube, it's all up to you man, whatever colors your like, but I would go with red and black.

And BTW, Paint will always end up chipping and coming off, so don't blame the paint if it does come off.