that happens to me sometimes, but there's always a reason. maybe you're just not conscious of the thoughts you're having that are causing you to blush?
Do you have anxiety? It happens to me because I am very fair. *shrugs* Is there a relation to your breathing? Make sure that you take long deep breaths and focus on your breathing whenever you feel your face getting hot. It helps for me.
Your face turns red because the blood is being forced to the surface when your heart beat is a little elevated, as in exertion or when you are excited. This happens a lot, especially in pale skinned, red haired people. Japanese men also turn beet red when they drink a lot, for the same reason - blood vessels close to the surface. Older people get this when they have high blood pressure - have you ever had your blood pressure checked? There is no real cure.
