Click/tap the Otamatone for a "Wah". (Or press space) Click/tap the buttons on the left to make the "Wah" longer or shorter. (Or press 1-5) Click/tap the arrows to make the pitch higher or lower. (Or press up/down) The blank button in the upper left corner switches between having the Otamatone making a "Wah" automatically or having to click/tap it. The P key is the pitch reset shortcut and the R key is the reset shortcut.
Otamatone sounds: https://www.youtube.com/watch?v=8pJ25vApCHo&ab_channel=TheRealSullyG