Instructions:

1. Pour 1 cup of your desired salt (or a combination of several salts) into a bowl (use either a stainless steel or a disposable bowl—plastic and glass bowls can sometimes get permanently scented by essential oils) 
2. Add 5-10 drops of your favorite essential oil or blend to the salt and stir together until no clumps of salt remain and the oil is distributed throughout the salt. Some oils that might work well either individually or as part of a blend are listed below.
3.  
   • Oils that are good for a calming or de-stress sea salt bath include: Roman chamomile, lavender, ylang ylang, sandalwood, holy basil, rose geranium, bergamot, neroli, cedarwood, frankincense, citronella, spruce, petitgrain bigarde, fennel, elemi, palmarosa,  pine, orange, fir needles, yarrow, rosemary, white cedar, lavender, spearmint, peppermint, balsam peru, rosewood, lemongrass, jasmine, Inner Peace, Cherub, Zest Unity, Serenity, Wisdom, Heart of Life, Humble Spirit, basil, Gabriel, Alleviate More, Fortitude, .
   • Some oils that would create a more invigorating or energizing sea salt bath include: cinnamon, jasmine, sandalwood, nutmeg, orange, rosewood, black pepper, grapefruit, petitgrain bigarde, Melissa, peppermint Tummy Rub, Endobalance, Heart of Life, Breathe Ease, Nightingale, Migra-Ease, Heart of The Forest, Gabriel, Wisdom, Exodus, Inner Peace, Dream Release, Unity, Trauma Release, .
   • Some oils that can be used to create a more romantic sea salt bath include: rose, jasmine, clary sage, rosewood, vanilla bourbon, bergamot, ylang ylang, Reassess, Muse, Existing,
   • Some oils that can be used to create a more muscle relaxant sea salt bath include: ylang ylang, roman chamomile, linden blossom, pink grapefruit, eucalyptus globulus, wintergreen, birch, black pepper, nutmeg, lemongrass, cinnamon, eucalyptus radiata, sandalwood, black seed oil, anise seed, valerian, fennel, petitgrain bigarde, cumin, eucalyptus citriodora, coriander, tangerine, Unity, Migra-ease, Relief, Breathe Ease,
   • Some oils that can be used to create a more Pain Relief sea salt bath include: clove, helichrysum italicum, wintergreen, nutmeg, black pepper, blue tansy, frankincense, vitex, peppermint. pennyroyal, oregano, roman chamomile, bergamot, rose balsam of Peru, cypress, balsam copaiba, lavender, cedarwood, eucalyptus radiata, eucalyptus globulus, black seed, cardamom, marigold, citronella, Melissa, valerian, spruce, ginger, celery seed, cumin, patchouli, eucalyptus citriodora, clary sage, fir needle, tarragon, marjoram,   Nightingale, birch, Release, Relief, Migra-Ease, Heart of Life, Healing, Trauma Release, Revision,
   • Some oils that can be used to create a more Cellulite Release sea salt bath include: pink grapefruit, rose geranium, wintergreen, cedarwood, juniper, tangerine, artemisia, sandalwood,
4. If desired, add one or two drops of coloring to the salt and mix thoroughly until color is evenly dispersed throughout the salt.
5. If you live in a humid area, you may want to spread your bath salt mixture on a baking sheet or a sheet of foil or parchment and let it dry for 4-8 hours (stirring occasionally). This can help prevent your mixture from clumping together.
6. Using a funnel, carefully pour your bath salt mixture into small decorative jars.   
7. Create a label or gift-tag that says what kind of bath salt it is, what the ingredients are, and how to use it (typically  1/4 - 1/3 cup of bath salts dissolved in warm bath water is a good amount). For example, your label or gift-tag might read:

Sea Scents Bath Salt: Contains natural sea salt, and pure essential oils of jasmine and cedarwood. Add one-fourth to one-third cup to warm bath water, wait until dissolved, and enjoy!

Extra Ideas

1. This recipe can be easily adjusted for different amounts, just keep the proportions the same.
2. If you are using a courser salt that may take longer do dissolve, you may want to make a small bag with a drawstring out of a fine mesh material to place the salt in. This bag can then be filled with the correct amount of bath salts and hung on the spout of the tub with the drawstring so that the bag is underneath the water that is coming from the spout. This will help speed the dissolving process, and will also keep the un-dissolved salt out of the tub.
3. Try layering different colored salts in clear glass jars to create some neat effects.