What to do for bruise like rashes on legs, butt, and arms that d not itch or hurt?

Ice and compression. Ice and compression to the area with a wrap. Bruising is below the skin bleeding, so elevating the area will help relieve pressure. Also, massaging the area gently while taking over the counter anti inflammatory meds. I hope this helps. If so, please vote for me. Thanks!
Please see. Please see your dermatologist for evaluation and to discuss treatment options. You may need a biopsy or other tests.