Let’s talk Glock undercuts. I see so many people doing their undercuts wrong or focused on the wrong things with their undercuts. I see people take the cut up super high and leave the sides square and leading to less than ideal ergonomics. The undercut doesn’t have to be taken up super high, it should be taken forward more than up and the edges should be rounded off. This allows for more room for your knuckles, and the rounded edges allow the fingers to come in quick and glide under the trigger guard without unnecessary discomfort and rubbing on a squared off edge. This is far more ergonomic and comfortable for all shooters than taking the cut as high up as possible. Some believe that taking it up high will result in the ultimate in recoil control. It won’t, and you’ve just made your trigger guard worse in many cases. If your recoil on a Glock is unmanageable you have a grip problem, not an undercut problem.
As with all things, these things take time. Practice and practice more.