Initially, I prefer that you spend the first 75% of your work out time on stretching and growing your chest voice.
Whether you are on my Volume 1, 2 or 3.
Then take the remaining balance, and start to connect the passagio from chest to your head voice starting off first very lightly to where you do not hear the yodle. (I call it the speed bump)
Make sure you use the same amount of volume when sing through the passagio as you do the rest of the scale (in other words, don’t back off the volume just before you get to the break and then sing louder after the break. Keep it all the same volume and only sing as loud as you can connect without hearing the register break).
Try to keep the sound bright (like the it’s the law vowel sound) and use the least amount of air as possible.
Connect with more than one vowel sound. This is important. A, E, Oh, Ooh.
Try to work up stretching the chest voice as far as possible before handing it off to the head voice.
Try to also connect on the way back down in the same place, connecting back into chest as early as possible (don;t drag you head voice down into your chest voice.
If you connect too early ascending a scale, or connect too late descending a scale, you will “weaken” that part of the voice and it will begin to atrophy.
The goal is to keep the chest voice robust and ready for belting as needed as high as possible.
Once you have achieved this, you will then (and only then) begin to connect at different parts of the scale learning how to “mix” chest with head voice.
This is the key to chest head mix.