Clean the surface before applying two coats of white paint, allowing each coat to dry for 10-15 minutes. After the final coat, wait for the paint to dry according to the manufacturer's instructions, usually a few hours. Next, sand the white paint with 600 grit sandpaper for a smooth finish. Finally, you can apply the clear coat, following the instructions on the can and allowing sufficient drying time between coats.
https://paintsgeek.com/flash-time-between-clear-coats-what-you-should-know/