It's quite an easy thing not to do tomorrow, as well.
Let's face it, the chances are you've never ever done any gyromancy at all, and never will.
Should you wish to (and I trust you won't) you must first make a big circle on the ground and draw the letters of the alphabet around it.
Then you must either spin round on the spot in the middle of the circle, or else run round the circumference of it, until you stumble or fall over.
Then you carefully write down the letter you've fallen on.
Eventually you either end up with a message:
for example; or alternatively you die or go mad.
Personally, if you're bored enough even to contemplate a spot of gyromancy, I'd recommend watching paint dry instead.
Thing Not To Do Today: gyromancy. This word derives from two Greek words: guros, which means circle, and manteia, which means oracle.