YOu need to do the rudiments. The boring stuff. If youre a baritone, youre gonna be near head at middle C on the piano. Certainly not chest voice. Maybe a "mid" voice but nothing lower. I would say any baritone would be in head by E. Baritone by definition is really NOT gonna get to the next B without straining. I would say around the G or A above middle C youre gonna start working around your falsetto break.
Noone is set in stone but this is a good place to start. Your lower falsetto can be very much like head. Just pay attention to the buzz at middle C. Middle C should be a strong lovely note for a baritone. Sing it and feel that buzz and tension. The "true voice" mechanism has your cords coming together in waves in particular shapes and speeds. Over a hundred per second. when you get to head voice youre still doing this just at higher speed So pay attention to the feeling and "buzz" or "ring" (which is the resonance of the vibratory pattern, and overtones, harmonics, etc) of this mechanism at middle C so you'll know whether or not youre feeling and hearing the same type of thing when you go up to G or A so you'll know that youre in head. You can't really sing falsetto early. Its not gonna happen. But you will have to relax and feel a since of letting go, "rolling up" or "flipping" into head voice. Its not the same feeling of straight out like mid and chest voice is. Some people skip over head voice because they can get this to happen, and you have to work to trick yourself into it. I don't think youre covering three octaves without access to your head voice unless you've got a hell of a falsetto. Remember three octaves of range is at least touching four octaves. Not just being able to sing three D's. But we've been over that before when people start saying "i've got five octaves" because they can sing into the fifth octave on a piano or something.
Falsetto is a result of pulling the cords thinner and not being able to keep them together vibrating in the wave. Remember to get a higher pitch your cords are thinning out and tightening in order to get this. So when you break into falsetto you've reached the end of your normal true voice mechanism(hopefully) and your cords are beeing pulled so much they cant stay together so the air is kinda cutting off the sides like a whistle, instead of making the cords wave. You will feel a difference and you will feel a bit more open. The sound is a tad more airy and the typical "girly" sound that guys make, i.e. Beegees or Prince.
Remember to think about the balloon. When you blow it up and pinch and pull the end to make it whistle and whine in various pitches. Thats basically how your cords are doing. And about the same relative thickness actually.
http://www.sputnikmusic.com/forums/showthread.php?t=219911
Merkabas Voice-Help Hotline - Music & Musician Forums