In a double boiler, melt the coconut oil. If you don't have a double boiler, you can use a large glass or metal bowl set over a pot of boiling water. Once melted, add the chamomile flowers. Place a lid over the top of the double boiler. Over medium heat, infuse the chamomile in the oil for 30 minutes.
Separate the chamomile from the oil by straining the oil through a fine mesh sieve and a light-weight towel or cheesecloth (to catch any little herb pieces). Discard the chamomile (or compost in a garden). Wipe the double boiler to remove any leftover herbs. Then return the oil to the double boiler. Bring the heat back to medium-high (enough to get the water underneath boiling). Add the shea butter to the infused oil, and stir until melted.
Once melted, remove the double boiler from the heat and stir the zinc into the oil and shea butter mixture. Once combined, stir in the aloe vera gel and lavender essential oil (if using). Pour the cream into a jar with an air-tight container. Store at room temperature, if your aloe doesn't require refrigeration.
Notes
To Use: Apply the cream, as needed, to a mild rash. Always spot test first before applying any cream (whether store-bought or homemade). Don't apply this cream to broken skin. For more information on preventing diaper rashes, check out Dr. Sears' article. This cream is not a substitute for medical advice.
The “where to buy” links provide links to the actual products I use. As always, I recommend shopping around online and at local stores for the best prices and products you love.