Stains that have been caused by tea and coffee can normally be dealt with by washing as soon as possible with a biological detergent. If your fabric is white and the stain is still showing then you can try dabbing the stain with hydrogen peroxide and water solution. If your hydrogen peroxide is a 20% volume then you need to dilute it to 1 part hydrogen peroxide to 9 parts water.

Always do the colour-fastness test before using bleaches. Never use bleach on wool, silk, flame resistant or easy-care finishes.