Old tablecloths, aprons and garments are lovely sources of fabric for various projects. Stains often come with old fabric and may prove challenging to remove. If you don't want to risk machine washing the fabric, you have a few options to banish the brown spots from old fabric. If your fabric has sentimental or monetary value, use caution when trying to remove spots and stains.
Determine what type of stained fabric you have. Natural fibers are more "fixable" than man-made fibers. Do a burn test if in doubt: Snip off a bit of fabric from outside a seam and burn it with a match. Ashes indicate natural fabric while melting indicates a man-made material.
Determine the color or print of the fabric. Bleach solid-white sturdy cottons. Soak colors and prints in non-chlorine bleach.
Rub a paste of baking soda and water with an old toothbrush onto the stain. Allow it to sit overnight. Rinse and repeat if necessary.
Apply commercial stain remover spray or stick, then let the fabric soak in cold water overnight. Rinse the fabric. Repeat if necessary.
Saturate the fabric with white vinegar or lemon juice, then use an old toothbrush to rub in table salt. Rinse the fabric. Repeat if necessary.
Hand-wash the fabric in mild detergent and hang it to dry if the stain persists.
Consult a dry cleaner as a last resort.