Congrats on the purchase of a new piece of gear. Can’t wait to hear your music with an additional effect.
I use my right foot just because the expression pedal is located to the right side of my multi effects processor. I’m so used to that, if I try to use my other foot, it feels awkward.

Find what feels right and comfortable to you. There are tutorials on youtube on how to use the wah pedal.

This can give you a basic idea. Click me