start fapping with the weaker arm?
actually, just make sure that both arms do the same number of reps/sets for each exercise and overtime, they'll even out. to do that, you either do exercises that use both arms at the same time (e.g. barbell curls) or you start single arm exercises with the weaker arm and stop at the same rep count with the stronger arm. yes, this technically slows the progress on your stronger arm, but unless you have a ridiculous strength difference between your arms, it won't take long for the other to catch up.