Pour a 1-gallon can of Behr semi-gloss enamel into a 5-gallon bucket.
Pour 1 cup of water in a measuring cup. Add the water to the 5-gallon bucket.
Stir the mixture thoroughly with a paint stir stick until the water is incorporated into the enamel and it is a consistent mixture.
Insert a screwdriver under the lid of a 5-gallon bucket of Behr semi-gloss enamel. Pry the lid off and observe the level of the contents.
Place a measuring tape on the side of the bucket from the bottom to the top level of the contents. Mark the center of the measurement with a nail on the bucket label.
Pour ½ of the enamel into a clean 5-gallon bucket. This will be the amount to leave the contents level at your mark on the bucket label.
Measure 2-1/2 cups of water in a measuring cup and pour it into each 5-gallon bucket. Mix each bucket thoroughly with a paint stir stick until it is uniform in consistency.