How do i take deodorant stains out of shirts without making a mess?

white marks or yellow pits? the white chalky stuff just rubs off, use a dry clean sock or rub the fabric against itself. the yellow underarm stains need a paste: baking soda, a splash of hydrogen peroxide and a drop of dish soap. work it in with an old toothbrush, leave it an hour, then wash as normal. do it over the sink and there's no mess. test the peroxide inside a hem first on anything coloured, and keep the shirt out of the dryer until the stain is gone because heat sets it.