strong flexible hairspray is always a good start. i like bedhead hard head hairspray.
sleeping on the side of your head, use a small pillow so your hawk can hang off the back and not touch anything, lay on your tummy and fold your arms above your head and then rest your head on your arms.. just gotta move around and find what works but is still comfy enough for you to sleep.
when i had mine it peaked at around 9". what i would do is take three pillows and put two down side by side and the other on the top of the left one. in a wau i created a cliff that the back of my hawk would float above. also i think subconsciously i also stayed put and avoided flop hawk.