A not very common but super useful creativity hack is NSDR - non sleep deep rest.

My favorite way to achieve that is Thai massage. You can rest, but there's still bodily movement, you are unlikely to fall asleep too often. You relax and don't push anything. Closed eyes recommended.

After the massage, I open my favorite mind mapping app and write everything down. Structure does not matter.

Why Thai? The quality and exact structure varies, you don't want to be too distracted by what's going on. Thai massage has the same structure anywhere in the world, so it's easier to practice this form of NSDR while nomading. If your tolerance for pain is too low, ask for softer massage.