To prevent blushing you can try the following things.
Drink less coffee; eat less energy foods and drinks as they can help the blushing come on a lot easier.
High blood pressure can make stopping yourself from blushing impossible so try cut back on the blood pressure .
There is a drug online called eradicane which is meant to prevent blushing but it sounds pretty crap from all the reviews I’ve read. Never tried it myself.
Some excesses can bring on blushing more than others.
Basically everything fun in life somehow makes you blushes.
Alcohol, smoking and marijuana is very bad if you want to stop blushing.
Visit for some more free info on how to stop blushing and a story of how a man cured his blushing. if you want some more info on rosacea visit http://www.nlm.nih.gov/medlineplus/ency/article/000879.htm for some good stuff