Well I have to warn anyone who wants to pet Cheech that he
will eat their fingernails if they have any. It must be the texture. I bite my nails myself so I don't need a chin to do it for me.
He'll also chew on my necklace if I forget to take it off and he's obsessed with plastic (even though it's very dangerous to chins).
I think the best advice I've been given here is to make a yelping noise if he bites you too hard so he learns you don't like it.
I think it's just a natural thing for them to do really, having constantly growing front teeth.
The best buy we got for Cheech was a parrot ladder. We put it horizontally in his cage to give him an extra little running space and he sleeps on there. He chews it to bits within a matter of weeks but they're so cheap we just buy him another one. Obviously check the wood it's made from, but that's really saturated his chewing needs. Oh, and anything cardboard, from tubes to just pieces of it.
Other than that I would just say, as one new chin owner to another, just give him a stern no if he's chewing something he's not meant to and a little push away if he still doesn't stop. Chewing wood in the cage is a natural thing I think. I'd be more worried if he didn't chew it.
Hope that helps.
And yes, he has groomed my hair. I find it really cute because he's not actually mine, he's my boyfriends and he loves my boyfriend to bits but loves to bite me all the time. He's our only one so he's really bonded with my boyfriend and I think he's jealous of me. :-[ But he has groomed me on occasion and then I'm even more honoured.