A stye can be caused by dirt, fecal matter or other debris. It is an infection of sebaceous gland on our eyelids. It will make our eyes red and swollen. To calm down a stye, you may need to clean the stye first. But I do not suggest you to do this by yourself for it really hurt and this may cause infections on other parts of our eyes. You may need to turn to an eye doctor.
I heard that warm compress can help cure a stye. The painful swelling caused by a stye is very boring. And sometimes a stye can affect our vision. If we make pus in the stye come out, the symptoms may abate more quickly. Warm compress can cause the stye to release the pus. You can dip a clean towel in hot water. And then wring it until it won't drop. You can hold the hot towel on your eyes for several minutes and reapply it until the pus won't come out. Hope this helped!