The expectation of being caught naked on your room will throw some adrenaline on your blood, and thus you play more aggressively.

Increment the risk (and thus the results) by using a random piece that will make you look more ridiculous than just naked. I usually put a belt on to face important battles, for example.

Bonus results if you live with your grandma. It doesn't work if there's nobody else in the house, though.