DIY How To Dye Fabric Using a Washing Machine from I Love To Create Blog here. This is a really short video tutorial (just over a minute). She uses Tulip brand dye (a major sponsor of tons of blogs) but I have used Rit dye in my machine to dye curtains. Always follow the directions for each brand of dye and use bleach to clean out your machine - not sure I would do this with a front loading machine.
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