If you have used glue, starch or other chemicals in it, I recommend washing it thoroughly in warm water and regular detergent and then doing a second rinse cycle.
I take mine to the laundromat and use the large front-loading washers that tumble rather than agitate. If they are not sufficiently "spun out" when you finish laundering, many laundromats have a separate machine that spins out moisture. If the quilt is very heavy after that (more common with cotton than polyester batts), you may want to dry it flat for a while until it is lightweight enough that you can hang it on the line without "stretching" it. Drape it across a couple lines rather than just hanging it from the top edge with clothespins.