This ritual started for me as a child. I published it in the now-defunct 'Hawaii Play Lei.' (That story was called 'Guitar Fetish')
Put a toy plastic ukulele (if you can find one) between your legs and put on some loud steel guitar swing music (Country-Western or Hawaiian)
Especially if you're a man-the friction of that instrument against your genitals plus the soaked-in, throbbing, orgasmic vibrations can drive you wild!!