I love making bath products, and here is a series of tutorials from Martha Stewart on how to make some of my favourites. Bath fizzies are always well received, and are pretty simple:
Bath Salts - a simple variation on the bath salts is to mix your salts, then open up a peppermint tea bag and mix in the dried mint leaves for a peppermint soak. This is a great refreshing soak for the feet after a long day of work.
Lip Balm - add a few drops of Vitamin E and lavender for a healing lip balm, or peppermint for refreshing balm.
Life With Monkey has a great tutorial for sewing your own hair curlers. This is genius!