Sorry if this is a stupid question, but I have seen people talk about boiling faux fur. I have a couple of questions...
1: What does it do to the fur?
2: How do I do it?
Thanks in advance! Floyd!

It makes it look matted and distressed. You put it in a pot of water and boil it. Nothing really elaborate about the process.

It seems obvious, but I would still like to be sure, you boil it before cutting and sewing it right ?

Yes that is correct.   I mean I guess you could boil a "skin" after you have cut it out and sewn it, but it is just easier to start with a hunk that has already been processed.

I did a few test with the fur I have (from puppetpelts), and I don't get any matted effect like I see other people do...

I've tried:
- 10 seconds in boiling water
- 2 minutes in boiling water
- Full hot cycle in the washing machine

And I dried everything in the dryer.
It was distressed but not matted, and when I ended up brushing it, it looked not much different than before boiling it.
Am I missing something ?

No your not missing anything. Furs well "matte" differently depending on their fiber content. Brushing fur well bring it back to life a bit although over time it won't bounce back. I think that furs are changing and improving so that they do hold up better to washing. Unfortunately while this may be good for most projects in this case it is hindering you. Give it one more hot wash and don't throw it in the dryer.  Just let it air dry. 

I wrote to puppetpelts, were I bought the fur, and they confirmed that this fur doesn't react to boiling.
Oh well...