The following is my own personal way of doing bathsalts. They make quick and easy gifts, and are great for those of us on tight-budgets. Your children will also enjoy getting involved.
Materials Needed:
stage 1 baby food jars (empty and cleaned)
1 bag of epsom salts (generally a 1-2 pound bag is fine)
food coloring
glue
squares of various material cut to cover the lids (2x2 suffices)
colored yarn (6-8 inch cuttings seem to produce a nice size bow but play around for desired effect)
Instructions:
Depending upon how many colors you want have one mixing bowl for each desired color filled with epsom salt. (Just divide the epsom salts between the various bowls).
Add drops of food coloring until desired color is reached. (Kids will have fun mixing the coloring in with the salt).
You can either fill each jar with one solid color or create layers.
Pop on baby food jar lid on.
Glue center of fabric square to top of lid.
Using yarn wrap the yarn around the baby food lid and tie in a bow. (This will give you the look of an old fashioned mason jar top that our grandma's use to put on their perserves. This part may be difficult for young children so a trick is to center the yarn yourself and glue it down on one side so all they have to do is tie the bow.)
As an added touch you can create direction notes and attach them as a name card (1-2 tsp per bath is nice).