Daily Warm Up for me has always started in the shower first thing in the Morning. I do glissandos from the highest falsetto note to the lowest basso. I then try to slow the glissando down with each repetition to even out the adjustment through the registers. Once accomplished, I continue the glissandos from top to bottom and then from bottom to top. I find the coffee before woke me up and the moisture loosened me up, so that I can do formal vocalises at the piano when dressed. What do you do to warm up?