Jump so high, you hit the ceiling and click resign.
Worst Thing To Do On Your First Move
Keep repeating, "Don't move until you see it. Don't move until you see it." for a while then say, "here, I'll make it easier for you." and sweep all the pieces off the board

Stare intensely at the board for 30 seconds and then mumble to yourself "Wait, this isn't checkers..." and then get visibly flustered as you storm out.

play 1.Nf3 then say "no I want to play d4" then your opponent says "touch and move!" then slap him on his face and play nf3 and d4 both

play 1.Nf3 then say "no I want to play d4" then your opponent says "touch and move!" then slap him on his face and play nf3 and d4 both
Get over it. We don't judge you for doing that.

Trying to handle stress from outside and accidentally pushing the board, knocking the opponent over, having them fall to another player, creating a chain reaction so unlucky, a meteor the size of Mars crashes Earth.
It's the best excuse for losing!
Ask, "How many points is it worth?"