Here is a simple glitch that gets you the crown on LittleBigPlanet 2.
Normally you would need the DLC but with this you don't.
First go and play the level 37 FREE COSTUMES PLUS DLC!!!!" Then after you've got the sackbot wearing crown object, go to create mode and go to your goodies bag. Now go to the community objects and place the sackboy with the crown. Then just hit square on the costume, now press X on costume. Then just save the costume and you'll have the crown as an costume!!!
Here's a video tutorial.
EDIT: IT STILL WORKS! JUST DO A TEXT SEARCH FOR THE NAME ETHAN0409!!!!
i am actually kind of glad that they patched this, it was fun having a crown but after about a week of people figuring this out it was rare to see somebody without a crown:\
It doens't really matter if it has been patched this glith doesnt seem to require going online all you have to do is get the costume from that level quit the game delete the game data then save it and redownload and install lbp2 back on