Often in pagan communities the topic of various homemade products comes up. Usually the conversation is more about homemade cleaning products, but sometimes the topic of skincare comes up as well, and whenever it does a lot of not so great suggestions for things to put on your face always seem to pop up.
One thing I find worrying is the idea that "if it burns, it's working!" You do not need to burn your face for something to be effective. The skin on your face is generally quite delicate, and treating it harshly is not a good idea. Of course, everyone is different, and some people can be a lot more harsh with their skin than others... so, before trying out any homemade remedy, or even any store-bought product, it's always best to do a patch test. To do that just use a small bit on a small area of your face, and see if there's any odd reaction in the next day or so. Some people repeat the test for a few days in a row, especially if they're prone to acne, as it can take a few days to really see if something is causing you to break out. Sometimes it's better to do the patch test on your wrist, especially if you're testing for any sort of allergic reaction.
Another thing to look out for is anything that makes your face feel very tight. A lot of people like that feeling and have come to associate it with being clean, or whatever else, but the truth is it just means your skin is too dry. Try something with a bit more moisture!
Now, what sort of things should you avoid putting on your face? I'd say avoid anything that has baking soda, lemon, and cinnamon. Baking soda is very basic, and is quite harsh on the skin, especially when used as a scrub. Using it as a scrub or mask is an especially poor choice for people with dry or acne prone skin. Sometimes a small amount of baking soda can be used when it's added to other things, but just using it straight, or using large amounts of it, isn't a great idea. Lemon is the opposite of baking soda in that it is too acidic. Additionally lemon and lime (and perhaps other citrus?) can make you much more sensitive to sun damage. That can either be a severe burn, a rash, or blistering. Cinnamon is a common ingredient in those "it burns so it's working!" remedies, but again, burning doesn't mean it's working - and many people are sensitive to cinnamon and can get actual burns from it.
If you're specifically making a scrub, avoid anything that is very coarse - nutmeg and ground nuts are commonly suggested, and not really that great for the skin on your face. A good scrub for your face would be something like a mix of brown sugar and a bit of olive oil. Be gentle with any scrub, and only use them a few times a week. People who have very sensitive skin or issues with acne should usually avoid scrubs.
What else is good? Honey. Honey is anti-bacterial and is slightly more acidic than the skin on your face, making it a good treatment for acne. It's also a humectant, which means it'll keep your skin nice and moisturized. It can be used as a mask, although it can be pretty messy to apply and keep on. Plain Greek yogurt can also be used as a mask. Apple cider vinegar can be used like a toner, but avoid white vinegar which has a lower pH and isn't as gentle to the skin.
Those are just a few examples of things that are okay, or not okay, for your face... and remember, everyone's different. There are apparently people out there who scrub their faces vigorously every day with baking soda and say it's amazing, but do your skin a favor and patch test, and maybe consider options that might be less harsh.
It's also good to remember that just because something is natural, that doesn't automatically make it good for you!