My formulas/recipe(s) are on about 5 pages of scribbled notes that would not make sense to anyone but me. I can give you a long list of my favorite links where you can find the means to DIY.
Here is a basic recipe for bronzing lotion that is similar to my sunscreen. I do not use preservative because that is the most toxic ingredient. It's necessary if you are going to sell it, because you need it to have a long shelf life. For my own use, I have added a drop of Vitamin E & grapefruit seed extract as a final step in making lotion, as a preservative and that has worked fine for me.
http://teachsoap.com/body-bronzing-lotion/
An article that explains lotion making basics:
http://teachsoap.com/lotion-making-basics/
My favorite source for bulk base & essential oils:
http://www.mountainroseherbs.com/index2.php
A good place to get zinc oxide, color oxides & micas for mineral makeup or tinting mineral sunscreen. You only need very small amounts of these. Mineral makeup is so expensive yet the ingredients to make it are cheap!:
http://www.coastalscents.com/make-your-own/makeup.html You can use these to make eye shadow, lip gloss etc. also.
I like these pigment blends as an initial base, since skin color can be so difficult to formulate. I add more brown or zinc, depending on my natural skin tone plus some mica like Opal Tan from the link above, to get the color that looks the best.:
http://www.makingcosmetics.com/Colors-amp-Color-Blends/Pigment-Blends-c21/
Another very toxic ingredient is emulsifier. I ordered AS102 because it seemed to be the most natural, but I can't find the link to buy it in the US anymore:
http://www.aquasapone.com.au/AS102-emulsifying-compound.html
Warning - This can be as addictive as chickens. I'm not even into makeup and all the girly stuff most normal women do, but I had a lot of fun experimenting and trying different ingredients to make lotion and sunscreen.