We always recommend performing a patch test before using any product on any client. The patch test is used to ensure your customer does not have any negative reactions to the product you wish to use. The test is simple and easy to perform during your consultations with clients.
1. Place a small amount of the product you're testing on the client's skin (we recommend behind the ear) and cover it with a bandage.
2. Instruct the client to remove the bandage the following day and check for any reaction.
3. If there is any redness or irritation, do not use that product. If there is no redness or irritation, that product should be safe for use on that client's skin.
If you have more questions about patch tests, this blog and video will help answer them.