Mix castile soap with oil and water.
Dip brush in makeup brush cleaner, swirling them into the cleaner until makeup has come off. You may need to use your fingers to break up any big chunks.
Once you feel like the majority of the makeup has been removed, rinse makeup brushes under cool water until the water runs clean.
Hang brushes to dry. Tying them together with a hair band and hanging them from a hook works well.
Allow to dry for 8 to 12 hours.
Use as you normally would.