I do shoot a VERY lite coat of latex primer. Some may
say that it's not needed but I find that I get much better
adhesion when I do so.

Make sure you use exterior paint and thin with distilled water.
Avoid using the color yellow if possible.

Very important.....make sure the paint is dry, (no oder) before
changing colors etc or before is sees gas or glo fuel.


Regards
Roby