I see so many post on racking the slide, especially for the shield.
Here is what I use and teach, I hope it helps some.

Racking the slide and not riding the slide forward is key to any semi auto. The technique I use and teach is to use both arms, not just one arm or the other. The more muscles you use the less each of those muscles has to work. When someone can’t rack the slide in the usual manner of grabbing the slide with their none shooting hand (weak hand) and pulling it back people always say instead of pulling back with the weak hand grab the slide with the weak hand and hold it, now push the pistol forward. While this might work for some you are just telling people to use a different set of muscles. Why not use both techniques rolled into one, Grab the slide as usual with the weak hand and pull back,while pulling the slide back with the weak hand push the gun forward using your strong arm. By using both you basically have twice the strength as you are using both hands/arms to accomplish this task. Now instead of letting go of the slide hoping it is all the way back just continue to hold on until you basically rip it right out of your weak hand. You will not be riding the slide or letting go before it is all the way back.
hope this helps