Hi Nikos,
i would start with factory preset 13:2, "Vintage Wah." This is set to be used with an expression pedal. But if you turn the Shape Knob to SINE then it will be an auto-oscillating wah.
Tweaking of the Depth and Xnob will change the character of the wah sound.
If you want to have it respond to your playing dynamics, turn the Shape Knob to ADSR or ENVELOP.
Then the Speed Knob becomes a Sensitivity control that lets you fine-tune how it will respond to your input level.
Alan