Adding buttons to control stepper motor speed.

Thanks Outside, so looking at the code, it uses the joystick proportions to determine the speed - correct?

I could also alter the params for the joystick position to determine the best & most accurate movement?

At which point in my code would I enter this. I'm guessing after the "void loop()" & remove the red code in my sketch below?

I'd still like to try the forward/reverse jog buttons & a rotary pot or 3 way switch just to compare accuracy, however I can't seem to find much info on how to do that.

Any help greatly appreciated as always.