Stubborn stains are frustrating to deal with because a simple wash isn’t enough. They may need to be treated prior to washing.
If you’re dealing with fresh blood stains, make sure to treat them with cold water. For dried stains, it’s a good idea to soak the fabric overnight in water using a special detergent. Treat dried grease stains by moistening them with turpentine and then dabbing with a cotton cloth. For ink stains, moisten the fabric with acetone and then use acetic acid.
In case you’ve got lipstick on your shirt collar, treat the stain with acetone, then apply methylated spirits. The best thing for red wine stains is to soak them in water and detergent, then rinse and treat with acetic or citric acid, and rinse again.