Samsara is right about there being lots of things to make. If you haven't yet, make a hammock or two. Tarps are the next needed item. You've got an UQ. Down is not terribly hard to work with, but do your homework first. Stuffing methods vary and some are neater than others. Don't stuff down anywhere you want to find some of it later.
Sounds like you've got the DIY disease. Congratulations! The DIY forum is chock full of stickies and tutorials. Scott at http://www.backwoodsdaydreamer.com/diy-guides/
has some good instructions and lots of material to work with.
What kind of sewing machine do you have? An old Singer?