Properly scrubbing your hands is one of the best ways to stop the spread of germs and viruses and to ensure you don’t get sick. But if you don’t have access to soap and clean water, or if you’re nowhere near a sink, you should carry hand sanitizer to protect your health.

As you’re no doubt aware, bottles of hand sanitizer (Purell, Wet Ones, and the like) keep selling out due to the ongoing Covid-19 pandemic. You can check these Amazon and Walmart listings to see if any are in stock, but make sure you’re not buying mass-manufactured sanitizer that uses methanol, or wood alcohol, which can be toxic when absorbed through the skin or ingested (check here to see hand sanitizer brands to avoid). Also, don’t drink the sanitizer, or any cleaning products, including bleach.

It may be hard to find that Purell, but making your own sanitizer is remarkably easy. You just have to be careful you don’t mess it up and that the tools you use for mixing are properly sanitized; otherwise you could contaminate the whole thing. Also, the World Health Organization recommends letting your concoction sit for a minimum of 72 hours after you’re done. That way the sanitizer has time to kill any bacteria that might have been introduced during the mixing process.

We actually have two recipes for you, along with links to find the ingredients. The first is one you can make with stuff you likely already have, so it’s effective in emergency situations. The second recipe is more complex but easy to make if you do some shopping and planning ahead of time. Another note: A lot of these items are quickly going out of stock because of high demand. There’s a higher chance of finding them at your local drug store, but your first priority is to stay safe.

Updated July 28: We added the FDA’s warning about methanol and refreshed the links and information in this guide.

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Potency Matters

You’re going to need some alcohol. According to the Centers for Disease Control and Prevention, your sanitizer mix must be at least 60 percent alcohol to be effective. But it’s better to get above that—aim for a minimum of 75 percent. A bottle of 99 percent isopropyl alcohol is the best thing to use. Your regular vodka and whiskey are too wimpy and won’t cut it.

The Quick (Gel) Recipe

Mix 3 parts isopropyl alcohol to 1 part aloe vera gel. Add a few drops of tea tree oil to give it a pleasant scent and to align your chakras.

The Better (Spray) Recipe