Help on sewing a bunny halloween costume!?

I was planning on being a bunny for Halloween this year (not the slutty lingerie kind, but more like a mascot suit without the head). Anyways the mascot suits are about $70-$200! I am going to try to sew this, although I'm not the best sewer. I am going to buy a white furry fabric and try to make a jumpsuit type thing out of it. How should i go about this? How do you sew this type of thing? What measurements do i take? Please please help. Thanks :)