Umm let's see…
I have a habit of saying a random word once (actual examples are chicken, Cheese cake, mustache, ect... some tend to be in other languages too and I don't even know why) then I'll use it like so often when I can't think of words for like 6 months or so, then I'll move onto the next word and it's rather odd xD (Another example, somebody says "What's that?" and I don't know so I just say "Cheese cake.")
I also have a habit of clearing my throat way too often but that's because of a medical thing I have ^^;
I unintentionally put my pinky finger up when I drink which has lead to people calling me posh, but I don't even notice when I'm doing it most of the time.
I only say thank you if I actually receive something, and it's not like I'm trying to be rude, it's just automatic. So if somebody offered me something and I declined I'd just say "No I'm fine~" but if I accepted I'd either say "Yes please" then thanks afterwards or "Yeah, Thanks~"
Oh and I tend to scratch my teeth when I'm trying not to laugh ~