There are three steps in order to successfully destroy a flag
Step 1: Ripping (a single incision to start the attack)

Step 2: Biting (Can be effective but swallowing large flags is difficult)

Step 3: Burning (Tried and tested. This usually finishes the job but can be dangerous for flag holder as seen below).

from here, here and here (Yahoo News)
September 8, 2006 at 1:11 am
[...] The flag biter is now chewing on the Chinese flag. The Chinese characters on the flag say ‘historical distortion’. From Yeolchae’s blog – [...]
September 10, 2006 at 8:31 am
They wrote down on the chinese flag. I hope they will not do that kind of silly protest anymore, especially with holy country’s flag, some of protestors, they just do it for fun, for showing anything to media,… shame,,,.
September 10, 2006 at 8:38 am
it’s just criminal, if he wants to kill himself, he’d better to do it without any country’s flag,,
October 21, 2006 at 6:42 am
[...] More on the flag biters exploits here and here. [...]