You will need to do your own laundry. Washing machines are not provided in Unit Lines. The usual Jamboree method is a bucket of water and some laundry detergent - the advanced version may include a plunger for agitation!
Remember all clothing (including socks & underwear) must have your name & Unit number written on them - a lot of clothing gets mixed up at a Jamboree!
If for any reason your sleeping bag needs washing, talk to one of your Jamboree Scout Leaders.