Cleaning your plaid comforter sets queen once a year or before storing keeps it cool and also helps the lint down to restore your attic. It can be dry-cleaned down, but it is expensive and some people are opposed to submitting their bedding to dry cleaning chemicals. It is cheaper to wash your down comforter in cold water. Use a front-loading washer that is large enough for your comforter. If the house machine is not a front loader or if it is not large enough, then take your comforter from a laundry with large enough machines.
Place the plaid comforter in the washing machine. Use a liquid detergent without dyes, stains, because they can stain the down. Measure and pour the liquid detergent into the dispenser. Set the machine to its most delicate cycle and fill it with cold water.
A time to end the wash cycle, remove the plaid comforter sets and put it in a sufficiently large amount dryer. Add the rings, drying balls to the dryer or a clean and washable canvas sneaker to help the lint down while it dries. Set the dryer to its lowest position. It will take a long time to dry and you will want to check periodically, making sure that the quilt does not ball in the dryer and that it dries evenly. Alternatively, you can hang your down comforter on a clothesline to dry.