Diet will be the most important factor, so make sure it's on point. If you need advice, you can ask for it or post-in/ read through the nutrition forum.
As for workouts, you could start cutting down your rest intervals to 30-45 seconds and maybe incorporate some circuit work to keep your heart rate up throughout the workout. Also, make sure you're doing your cardio after your workouts and keeping it intense. Personally, I don't believe there's much of a place for LISS if you're trying to hold on to your muscle while losing fat (naturally). Experiment with interval training - short and sweet, but it should be hard as ****.
Get after it!