We recommend mixing small batches (about a quart to 1 1/2 quarts) until you are sure of your technique and adjustments of your spray gun. The product usually has about 15 minutes potlife in this quantity which is ample time to apply small amounts. The potlife reduces with larger quantities since the product can maintain the heat it is building up as it cures. Once you are familiar with the process, you can mix larger quantities since you can apply more quickly. Remember to always clean most of the uncured product out of your reservoir and gun before starting to mix the next batch to avoid clogging your gun.