Making your own bath fizzies at home is not very complicated. You have the cost advantage along with avoiding artificial fragrances and dyes compared to the ones you can buy from shop.

Ingredients:

1 cup Baking Soda
2 teaspoons olive oil
1/2 cupSea Salt or Epsom Salt
Essential oils or powdered dried herbs (ginger is great)
1 teaspoon vanilla extract (or more water)
2 teaspoons witch hazel (or water)
1/2 cup Citric Acid

Method:

Combine baking soda, salt and citric acid and mix well until combined.
In a small bowl, combine the olive oil, witch hazel and vanilla extract and stir well. Add essential oils if using.
Add the liquid ingredients to the dry ingredients and very quickly mix well with hands (wear gloves if you have sensitive skin). Add powdered dried herbs if using.
Mixture should hold together when squeezed without crumbling. You may need to add slightly more witch hazel if it hasn’t achieved this consistency yet.
Quickly push mixture into silicon molds, greased muffin tins or any other greased container. Press in firmly and leave at least 24 hours (48 is better) or until hardened. It will expand some and this is normal. You can push it down into the mold several times while it is drying to keep it from expanding to much.
When dry, remove and store in air tight container. Use within 2 weeks.