This has proven to work on 2 people so far - my son and his friend.
What I write is based on personal battles. Before I learnt Yoga and became a certified Teacher to help my son, for some 3 years in stretch, I had Migraines. Those days, I learnt that going out for fresh air helped.
Then my son battled with Migraines because of his history of the Head Injury. What I told him did work magically finally but in the beginning it did not work as well, as I was not sure of the correct method, and initially I would make him do Kapalbhati as well. But Anuloma-Viloma actually really works with some modifications.
So what you do is, go outside in fresh air, and do Anuloma-Viloma, but here you try to hold the breath as long as possible. Do it over 10 to 15 minutes. Have patience and your Migraine should go away.
If does not, you may want to consult doctor for issues like Bad Eye Sight, Glaucoma, Brain Tumor and other issues. Please make sure your are having adequate sun, lighting (to read), fresh air, water, nutrition, and good restful sleep.
Tension Migraines would benefit from the technique I have mentioned, and Meditation and Calming Techniques of Mind would also help here.
Please check for Anuloma-Viloma and Meditation techniques mentioned in the Blog.