... Harry could feel his face burning. Snape was pausing at the end of every sentence to allow the Slytherins a hearty laugh. The article sounded ten times worse when read by Snape. Even Hermione was blushing scarlet now.

“'…Harry Potter's well-wishers must hope that, next time, he bestows his heart upon a worthier candidate.’ How very touching,” sneered Snape, rolling up the magazine to continued gales of laughter from the Slytherins. “Well, I think I had better separate the three of you, so you can keep your minds on your potions rather than on your tangled love lives. ...

I don't quite understand the part in bold above. It might be because the use of 'to' is confusing. "rolling up the magazine to" doesn't seem to make much sense to me. How should we understand it?