Any secrets on how not to blush in public speaking?

I always go really red and my face turns hot when im doing a speech or something and its annoying, any homemade remedies or something like that?Any secrets on how not to blush in public speaking?
i think breathing techniques work for me, before you go up tell your self theres no need to be embaressed and what you have to say is worth listning to. if you feel your starting to go red try to imaging something cold like ice across your face!!....dont be ashamed everyone goes red sometimes i always do...alternatively you could make a joke about it by saying something like '; i can feel im going red now then laugh a little'; laugh it off and you'l soon become more comfortable!! i find it cute anyway xx