On large surfaces, such as a flush door, dampen the surface with clean water prior to painting. This will help the paint flow and extend the drying time. Do not over soak/wet as this can result in reduced adhesion and water streaks.
Apply a generous coating (adhering to spreading rates), laying off as you go. Once laid off, do not apply any more paint or re-brush the surface as this will lead to flashing and will increase brush marks. Apply two coats of gloss as this will give you a higher sheen level.