scales,thats how every proffessionalwarms up my friend,using scales.
the major scale is a good place to start then work your way up by haf steps until you reach a point that is almost uncomfortable and out of your range then decend.
and remember to have clean transisition going from your chest voice to your head voice,keep them the same,head voice is falsseto either so dont cheat my switching to falsseto thing thats your head voice.
push yourself and you will be betterthen you have ever dreamed.
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