Ivanessa, I am sorry that you are experiencing some
frustrations. It has been a long time since I watched Greg’s video on shape
change presented in the Largo Fundamentals (Leadpipe – Shape). I was pleased
that he has expanded the notes beneath the video.

SHAPE consists of:
Lips,
Jaw,
Facial Muscles,
Tongue Position.
Pitch change comes from SHAPE change.

Hopefully, you have practiced with the leadpipe. If you do not have one and do not have a large straw, you can pull out your tuning slide and use your horn’s leadpipe. This is a great place to learn about beginning shape change. Greg, at this point, is having the student focus on the aperture corners. As you get higher and lower notes on the instrument you will use more jaw and tongue changes. The changes in the tongue and jaw can be understood using the vowel sounds such as aww (tongue down, jaw down) and “eee” or using the vowel sound in the word “it” (back of the tongue raised and the jaw more closed.), For now, focus on the lip’s aperture corners. When Greg plays extreme low sounds on the leadpipe and much higher pitches, he is using a combination of all the factors of shape change to be given in later lessons.

How to know if you are clamping.
Make the “m” sound as in “moo”, the lips are together.
If you then were to muscle the lips together as if you were trying to keep someone from giving you some nasty-tasting medicine in a spoon, that is clamping. If you were to complete the word “moo”, you have something very much the same as Greg’s “ahh-oo” aperture. The lips are not clamped and the middle of the lips has a nice opening.

You may have read Greg’s “The Premium Level” ad before “The Largo Singing C Series”. You will notice
he says you get, “get MTM eBook 1 (PRINTABLE) and lifetime access to the interactive eBook”.
The “MTM eBook 1” is written for beginning trumpet players. Using it along with WindWorks could possibly help.