During the summer in my high school years, I would often struggle with insomnia for some reason. I would get frustrated with myself for sleeping at 3am when I didn't have school.
Back then my online friends would suggest me to "daydream of yummy food".
Though regardless of what I did, it didn't really work. At the very least, I slept around 3am and woke up at 11am. To 16 year old me, that was frustrating to deal with.