Note, proper hand washing is the most effective way to prevent the spread of germs! Hand sanitizer should not replace hand washing. I only made some so that I could bring it on grocery outings. I made an entire quart (32 oz) for $3.87.
To make hand sanitizer, you need alcohol (the FINAL concentration of the alcohol in your finished product needs to be around 70%) and a base, such as aloe vera gel or glycerin. The base protects your hands from drying out.
Aloe vera and glycerin are out of stock everywhere, so I bought a huge aloe leaf at the grocery store. I already had rubbing acohol with an alcohol content of 91%. You can't use vodka or anything from the liquor store because the alcohol content isn't high enough.
I cut up the leaf into segments, as shown in the picture below. It was easy to get the gel out of each piece using just my hands. I got approximately 1 cup of gel.
Next, I added 3 cups of rubbing alcohol, which was the amount needed to ensure that the final product had an alcohol content of 70%. Finally, I used my immersion blender to mix everything thoroughly. You could use a regular blender too.
The final product is...not like the commercial varieties, but it will work in a pinch. It's thin, and the gel didn't mix well; I'll have to shake it before every use. It was fun to make though, and I really didn't have any other options!
cost per batch (32 oz)
24 oz of rubbing alcohol (91%): $1.88
1 aloe leaf: $1.99
total cost: 3.87