If you are going to use two coats make sure you have the right resins. Some finishing resins have a wax additive to help them cure to a hard finish. If you overcoat them you get the dreaded fisheyes.

I use West system 105 with the addition 410 lightweight filler for the second coat.

Wash down the first coat with warm water then repeat. If there is the slightest sign of the water beading up you have contamination. Wipe down with acetone and repeat the water test.