1. Inventory. Go through your bathroom, handbag, drawers, and cabinets. Line it all up on the dining room table, on the floor of the living room, wherever you have room. What you have will probably be somewhere between "just shampoo, hand lotion and chap-stick" and "it looks like a beauty-supply store in here."
2. Edit. What do you actually finish and buy again? What are the items you've used only once? What is spoiled?
3. Cull and recycle. Toss the old and manky and see if you empty the containers to clean and recycle or reuse them. Look closely at the once-used - can you pass it on to someone who would use it?
4. Keep and evaluate. Look at what's left. For each item, think about what you like about it. What does it do for you? What do you like about it? What is the cost in your money? What is the cost of manufacture, delivery and storage?
5. Reverse-engineer. Look at the list of ingredients. Research what they are and what they do. It is very possible that most of the ingredients are either something you can obtain pretty easily or don't have a big impact on the way the product works.
6. Make a list. Choose one or two products you'd like to try to make. Look on-line, at the library, or buy a book on how to make color, bath and body products at home. Select a formula. Determine what ingredients and packaging you need and obtain them. This can be as simple as buying a few things from the grocery store or as complex as researching online hand-made bath and body suppliers, which actually isn't that complex.
7. Make time. Mark out a couple of hours to create your products. Usually, the kitchen is best. Sometimes having a friend or two working with you is fun, and it can be economical to share supplies.
8. Enjoy. Creativity is satisfying, particularly when it yields something you can use.
My suggestions for your first projects
Lip balm - Very basic: Soy oil, beeswax, old lip-balm tube or pot. You can add - flavor, other oils, mica for small amount of shimmer.
Lotion - Very basic: Water, soy oil, borax, beeswax. You can add scent, color, mica. Step up to improved texture and performance by using an emulsifer from a lotion supply company.
Powder eye shadow - Very basic: Mica, a small jar or tiny zipper bag. You can also use powdered mica as liquid liner by using with with a wet brush.
So you want to try to make your own. How do you start?