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Alum blocks are becoming more common in the US. You can now find them at many drugstores and beauty supply stores. If you're not sure where to look, ask an employee.  You can also purchase an alum block online. Typically, they cost around $20. Many people consider this a good investment, as an alum block can last for years. Make sure to purchase a block that is pure alum. You do not want additional ingredients. After you shave, you need to prepare to use the alum block. This means getting your face (or legs) wet. Splashing your face with cold water helps close pores and allows the block to easily glide over your face.  Alum blocks are most effective as a post-wet shave product. Make sure to thoroughly rinse all of the soap or shaving cream from your face. This will further make it easier for the block to glide over your face. Simply run the stone back and forth under the faucet. Make sure the entire surface is wet. Some people like to soak the alum block in ice water before use. Beware: this can increase the tingling feeling you will feel during use. Rub the block onto the areas of your skin that you’ve shaved. You can also apply the block to other areas of your face or body. Remember, an alum block is known for its astringent qualities.  You can expect to feel a little bit of tightness and perhaps some tingling. Don't worry, this is normal. While most people just use alum block on the face, you can apply it elsewhere on your body. For example, you could rub it on your legs after shaving. If you’re new to shaving the block can be a good indicator of areas where you might want to improve your shaving technique. The alum block has a tingling or stinging feeling so areas where the stinging are high usually indicates that too much pressure is being applied in that area with the blade. Take care to be more gentle on those areas next time.  Rinse off with cold water and pat face dry with towel. Some people prefer to skip the rinse and just leave the alum on the face. You'll continue to feel the tightness for a few hours, but it shouldn't be uncomfortable. It is essential that you allow your alum block to dry completely before putting it away. Your block won't be effective anymore if you put it away wet. It can take several hours for your block to dry. Try leaving it on the counter to air dry while you are at work.
Purchase an alum block. Wet face with cold water. Wet the alum block in cold water. Glide alum block across face. Evaluate your shave. Dry your alum block.