How can acetic acid be safely used on the skin for its benefits?

Acetic acid, commonly known as vinegar, can be safely used on the skin for its benefits by diluting it with water before applying it as a toner or spot treatment. It is important to perform a patch test on a small area of skin first to check for any adverse reactions. Additionally, it is recommended to avoid using undiluted acetic acid on the skin, as it can cause irritation and damage.