Measure the dried pine needles into a spice grinder or small food processor, process until it's a fairly fine powder.
Measure your Epsom salt , baking soda, and pine needles into your plastic baggie, along with colouring if you're using it
Use an eye dropper to measure your essential oil into the ingredients baggie.
Press most of the air out of the bag, and close the zipper on it.
Manually crush any clumps in the salt, and work to combine the ingredients.
Transfer mixture to an airtight container, or measure into bath tea bags.
To use, measure 1 cup of Citrus Cedar Bath Salts into a hot running bath, or toss one bath tea bag in.