The best way to care for your cloth pads is to dry store them after use, either in a water proof bag or bucket.
On wash day soak your pads for 1 - 12 hours prior to machine washing in cold water, you can use an oxi cleaner if you wish to.
Wash your pads in your machine on a 20-40c cycle with a powder detergent, no hotter as hot washes are likely to set stains.
Avoid fabric softener as this coats fabrics and prolonged use will effect the absorbency of your pads.
Preferably air dry your pads or tumble dry only if your dryer has a low, gentle heat setting