Combine ingredients except zinc oxide in a pint sized or larger glass jar. I have a mason jar that I keep just for making lotions and lotion bars, or you can even reuse a glass jar from pickles, olives, or other foods.
Fill a medium saucepan with a couple inches of water and place over medium heat.
Put a lid on the jar loosely and place in the pan with the water.
As the water heats, the ingredients in the jar will start to melt. Shake or stir occasionally to incorporate. When all ingredients are completely melted, add the zinc oxide, stir in well and pour into whatever jar or tin you will use for storage. Small mason jars (pint size) are great for this. It will not pump well in a lotion pump!
Stir a few times as it cools to make sure zinc oxide is incorporated.
Use as you would regular sunscreen. Best if used within six months.