looking for advice on improving endurance

Hi, I typically identify as a femme dom, but recently I’ve been exploring the bottom role and am looking for exercises or stretches that can help with endurance and mobility. Lately, I've been noticing some stiffness in my hips, and while stretching helps a bit, I feel there’s more I can do to improve. Any tips on exercises or routines that have worked for you? I’d really appreciate your advice on how to build endurance and increase flexibility for better comfort and mobility.