Hi, Mr. JAY AND THE READERS OF THIS BLOG
My preferred method of labial pronunciation lies in coordinating tongue, to forward, mid and soft palette positions. This is secondary to the ventriloquist artist in training the lungs to fill low to high instead of lifting the chest before filling the abdomen. In that way short or long breaths have a good source from which to draw to create the illusion of breathing from two points so as to create the fantasy of a dialogue between two or more characters. I'm not too enthusiastic about earlier methods of substitution since tongue tip to palette can and do produce labials whose sounds are barely indistinguishable from that produced by the lips. That said; how we hold the brush to the canvas, so to 'speak', pardon the pun, will differ slightly artist to artist. Give the jaw a consistent anchor point. you can study this effect in work by Paul Winchell, Shari Lewis, Jimmy Nelson...or today's Jeff Dunham or the artistry of actor Jay Johnson.