Choose one or more of the following organic botanicals (available at MountainRoseHerbs.com):
Rosebuds
Calendula flowers
Lavender flowers
Peppermint leaf
Chamomile flowers
Oat tops
Passion flower
Comfrey leaf
Hops
Cleavers
Ginger root
Holy basil leaf (tulsi)
Lemon balm leaf
Red clover blossoms
Rosemary leaf

Mix your choice of herbs in a jar. Fill a drawstring muslin bag with the blend and drape over the faucet so hot water runs through the bag and creates a tea in the tub. Once the tub is full, toss the tied bag into the water and swish it around to infuse your bath with even more herbal goodness. Another method is to make a large pot of tea using your herbal bath blend and add that herbal infused liquid to the tub before getting in to soak.