I use different size balls to help me w/ tight muscles. A really excellent type for the areas you're talking about, is a soft-ish rubber ball for toddlers, about the size of a grapefruit, with raised 'spikes' to make it easier for little hands to grasp. I put mine into a sock for comfort. Then lie on it and let your body sink into it. Both relaxing into it, and rolling around with it a bit, maybe making very small circles of your shoulder blade on top of it. Play with it. When you remove the ball and lie flat, you'll be amazed by the change.
You can try with smaller ball, like tennis ball, or, for hips, something larger, soft beach ball the size of soccer or a bit smaller. Racquette balls are wonderful for rolling around under your feet, to wake up balance receptors and remind the foot that it's not a solid, fixed mass, but has depth and springiness.