DIY Air Freshener. To do this project you need a small mason jar, cheesecloth, baking soda and essential oil. Essential oil can be purchased at craft stores and health food stores and GNC. Just spoon about an inch of baking soda into the mason jar and add 8 to 10 drops of essential oil. Cover the lid with cheesecloth and screw on the band. Trim away any excess cheesecloth. Tie a ribbon around the band, or pop it into an pretty organza bag.