Important Notes    

This recipe is for the most basic, bare bones bath salts you can make. It also makes a very small batch. It is easily increased, just keep the basic proportions the same.  Exact amounts are really unimportant. You can use a slightly larger proportion of salt, but never use more baking soda than salt. Some people don't even use baking soda at all. Sea salt can also be added.  I always include glycerin in my salts. Glycerin boosts the skin softening properties of your salts. It's available at drug and health food stores, but if you use it often I suggest you purchase it in larger quantaties on the internet.

Some recipes include Borax such as Twenty Mule Team in the mix. As I understand it, the borax prevents a film on your tub.  It's often required in bath bombs, but unnecessary in salts unless you include fixed oils. Fixed oils include Sweet Almond Oil  (my favorite), Apricot Kernal Oil,Coconut Oil and others. These oils can be added in small amounts to bath salts. They are great skin softeners, but your salts will be more likely to leave  bathtub ring.

As for coloring, it can be left out, you can use plain old food coloring, or colors made for soaps and cosmetics.  I use the ones made for soapmaking as they go far and the selection of colors is nice. They are available at your local craft store. Food coloring works nicely, but often when trying to get a color like purple, you will end up with some pinkish grains and some blue ones. However, I have done this and found the results attractive. Don't worry about staining.  Most salts only lend the slightest tint to the water and won't stain your tub. Think of it as putting a couple drops of color in your tub. It's really not much.

Now, what I consider the most important ingredient in bath salts.  Fragrance! It would be bath salts even if you put a half cup of epsom salt in the tub. Don't scrimp here.  Buy the best you can. Essential Oils, the volatile oils extracted from plant materials are best. They are strong, go far, and don't fade. They cost more, but are worth it. Especially if you want one pure note like lavender.  Fragrance Oils are blends of aroma components that are created to smell like the real thing.  Sometimes they contain essential oils. They are less expensive and available in a wide range of scents. If you want something like cucumber melon, you will have to go with fragrance oils. They are also available in specialty scents such as cotton,  popular combinations, and copies of famous scents. They won't give you quite the heady experience of the essentials, but are fun and fine if you don't plan on storing your salts for very long.  The little sample vials of perfume given out at department stores can also be added.  They will often slightly discolor your salts, but they are free.

As for containers, be creative. Just remember the salts must be protected from dampness. Sometimes in a jar near the tub they will clump. Just shake to loosen them.  For personal use, I have a pretty jar in the bathroom and refill it from zip lock bags stored in the linen closet.  For gifts, I often use the cellophane bags sold for goodies tied with pretty ribbon . Dollar stores and flea markets have all kinds of  pretty containers that are very inexpensive. Keep an eye out.  A pretty scoop tied on makes the gift special and easy to use. I get these at Bath & Body Works and World Market. Sometimes they are available at kitchen stores. For little over a dollar, they add so much. Attach a pretty card with instructions too. Find some pretty clipart and you can print these out in minutes. Jars can be labeled. Print or make with plain paper and use a glue stick to attach. Pretty soon you'll be churning out bath salts better than any you can buy and at a fraction of the cost.