To catalyze TotalBoat Polyester Laminating Resin, at 77°F, add 7-8 drops of MEKP catalyst per one fluid ounce of resin. You can measure the fluid ounce(s) of resin in a clean mixing cup. If you're doing a larger project and counting drops of catalyst is not an option, base the amount of MEKP required on the weight, not the volume, of the resin. Specifically, use approximately 1-2% MEKP catalyst, based on the weight of the resin; note that one gallon of polyester resin weighs about nine pounds. To manipulate the working time and cure rate in your favor, you can adjust the amount of MEKP by adding less catalyst in warmer temperature conditions (more working time, slower cure), and more catalyst in cooler conditions (less working time, faster cure). 

MEKP Catalyzation Chart (based on polyester resin weight of approximately 9 lbs. per gallon)

WARNING: Do not add more than 3% MEKP catalyst, maximum, or the product may not cure, or the laminate produced could shrink, deform, or be hard and brittle after being demolded.