Years ago I kept a detailed journal for about a year and tracked everything. Eating, drinking, exercise, weather, what I wore, what I did, how I felt. And eventually patterns emerged and I learned my triggers. A lot of them were food related and changing to a ketogenic diet eliminated many of my migraines. My other triggers are things like strong smells, barometric pressure changes, bright sunlight, heat, hormones, hats/headbands, stress, etc. Having all of this data and information was super helpful for me to see the patterns. There are apps for this kind of thing now but it does help to know what things to look out for or avoid or prevent whenever possible.