Most people weigh themselves when they want to lose weight, but using a scale is a great tool for tracking muscle gains too. Weigh yourself once a week on the same day and time, preferably first thing in the morning, after you’ve used the bathroom and before you’ve eaten. If the scale isn’t moving up, you’re not gaining muscle. Plain and simple. Shoot to add about a half-pound per week to minimize fat gain and use the mirror to make sure the weight you’re gaining is solid muscle.