How do steel the Santa hat from the crab runescape 2010?

Answer 1

In the fifth room, you need to click on the right crab when they pop up five times until you can catch it. When you speak to Santa, he will not be able to take the crab out of the bucket so he gives you the whole thing instead as a reward. You should be able to equip it.

So basically, you don't steal it whatsoever. You wear it on you with the crab aswell.