Use a comb or your fingers to pull out as much hair as possible from the brush. For stubborn hair, use scissors to cut through and remove it.

Fill a bowl or sink with warm water.

Add a few squirts of liquid Castile soap to the water. If you are using a bar of Castile soap, you can grate a small amount into the water and stir until it dissolves.

Submerge the hair brushes in the soapy water. Let them soak for about 10-15 minutes. This will help to loosen dirt, oils, and product build-up.

After soaking, use a toothbrush or a small brush to scrub the base and bristles of the hair brushes. Pay special attention to areas with heavy build-up.

If the brush has a cushioned base, avoid fully submerging it to prevent water from getting trapped inside.

Rinse the hair brushes under running water to remove all soap and residue. Make sure to rinse until the water runs clear and there are no soap suds left.

Shake off excess water from the brushes.

Use a towel to blot them and remove as much water as possible.

Lay the brushes bristle-side down on a dry towel and allow them to air dry completely. This might take a few hours to overnight, depending on the brush type.