There are a few things you can try to relieve a sinus headache quickly:

1. Apply a warm compress: Placing a warm compress over your sinuses can help to alleviate pressure and reduce pain. You can use a damp towel or a heating pad set on low.
2. Use saline nasal spray: Saline nasal spray can help to clear out your sinuses and reduce inflammation, which can relieve your headache. Simply spray the solution into your nostrils, one at a time.
3. Drink plenty of fluids: Staying hydrated can help to thin out the mucus in your sinuses, making it easier to drain. Drink plenty of water, and avoid beverages that can dehydrate you, such as coffee and alcohol.
4. Try over-the-counter pain relievers: Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, can help to reduce inflammation and alleviate pain.
5. Use a neti pot: A neti pot is a small device that you can use to rinse out your sinuses. Fill the pot with saline solution, then pour it into one nostril and let it drain out the other.
It’s important to note that if your sinus headache is severe or lasts for an extended period of time, you should consult a healthcare professional.