How do I make an item bobble and wobble like the bloonicorn?

[Brown]

I made a hat that floats right about the engineers head, but the problem is that i want to make it wobble like the bloonicorn. I know that i have to assign it to a bone then edit the qc file to let it do so. But what bone do i need to assign it to and what should the qc codes look like?
Also what is the best program or way to get pictures to have on the items workshop page? Ive heard that source filmaker is the best thing. Is it?

Thanks!

[HellJumper]

Check out this video:
http://www.youtube.com/watch?v=JP9ce_ygeSA

The half-life model viewer and source filmmaker are the best ways of doing that.

[Brown]

Thank you for your help a lot!!
Do you know any good videos that explain the source film maker?
And also i watched that video but i was just wandering if you just already knew the qc file to make it like a bloonicorn...i guess ill just experiment and find out