How can make a DIY solution for getting rid of fleas?

Here is a recipe https://www.hometalk.com/diy/clean/diy-dog-flea-spray-no-chemicals-1675114

DIY Dog Flea Spray - No Chemicals

I'd just like to add that you need to make sure the fleas have been taken care of on your pet first before cleaning your house, and that you'll need to clean your house in a couple of waves as the eggs from the now-dead fleas hatch and new fleas emerge. It's an ongoing battle, but you can do it! For my pets, I usually like to use an oral or topical treatment. See what your vet recommends.

I have heard of....There is a "catcher" you can make with a light bulb (short lap), a shallow dish, and a squirt of dishwashing liquid. They are drawn to the light bulb's heat, and they drown in the water. Be careful not to allow the light to get in the water. Someone may have used this method. But vacuum your house 2 times da y helps to get them and their eggs out.

Put borax in a salt shaker and sprinkle all over the carpet. Let it sit for a couple days, vacuum, then re-sprinkle again. The borax dries the fleas & eggs. You might have to do this more than twice. Also treat the cats & dogs at the same time.