How to make you own bath salts. Use what herbs you have growing in your yard. Get a big glass container with screw on lid. Layer sea salt, herbs, sea salt, herbs in that order and make sure salt is first layer and last layer. Screw lid tightly and put in cool darkest place you have. Leave for a couple of weeks or months for that matter. Take the jar out and remove all herbs. Put the great smelling salts in decorative jars and screw lid on and these make wonderful gifts.