Wash or Dry Clean Curtains?
As with most things, check and read with care, the instructions to decide
Some are made of washable material, but the linings and the threads used in the sewing may shrink in water, thus if in doubt, Dry Cleaning is the best option.
Window Curtain with pleats, or other ornamentations should go to the dry cleaners.
If you go with machine-washing use the gentle cycle, with cool or lukewarm water, and mild detergents to be on the safe side.
Remove Dust from Curtains
Get out the ruler and measure curtains first, do this; in case you need to stretch them back into shape, so remove hooks and such, lie flat and measure.
Next, it would be a good idea to "remove dust from curtains" before any kind of washing, this can be done either by putting them in the dryer, on the "no heat" cycle.
Another method is to shake drapings outside, lay on a flat surface and use the vacuum brush attachment to suck up dust particles or if you can take drapes down with ease, then air them outdoors on the clothesline.
Don't forget the curtain/drapery cords, which normally can be cleaned easily, by using a dust cloth on instead of wetting them as this could cause the cords to shrink.
Prepare Curtains for Washing
Check for any loose attachments, strings or tears and either mend them first or remove.
If you decide to hand-wash, refrain from rubbing or wring the fabric; just gently scrub and softly press out water, and when hanging dry don't let curtains rest on surfaces that may bleed or on wood which may produce stains.
Don't overload the washing machine, it better to put the cycle on full or "large" load to give plenty of room to circulate, as curtains often become heaver when wet.
Drying / Ironing Curtains
Remove all hooks, metals, etc, and when material is dry replace hooks, check measurements and re-adjust if needed.
If ironing damp curtains, do so along the vertical side that doesn't show, make sure to dampen the entire
Before hanging curtains back up, make sure to clean valances, by using a vacuum for upholstery valances, for wooden use the vacuum crevice tool; to clean a plastic valance use a sponge with a mild bit of liquid detergent and water.
When ready to rehang, have someone there to help you; one person standing on a ladder to replace the hooks and you or the other person stand below to make sure material doesn't drag on the floor.
Okay there it is, now go wash those curtains !