Mixed Voice

Hello everyone, I have a question regarding mixed voice. So Ken says to first stretch chest voice, then strengthen head voice, then strengthen the Passagio ,but how do I know when my chest voice and head voice are well developed. My chest range is from A2-G4 and my head voice can go up to a F#5. Until what notes should I stretch my chest to and how low should I bring my head voice ?
Comments
when I started the course, Ken would be talking about moving over into head voice, but I couldn't hear any difference with his voice, (because he's developed it so much). I didn't realise I didn't have a head voice until one day it suddenly appeared!
But the problem is that my head voice is very flutey, and a very different sound to my chest voice. This is an opportunity for development.
Likewise, as I get to the top of my chest voice range, the sound quality changes: it's an audible difference.
So the aim is to develop both of these, so they become strong, and then are indistinguishable. But this is a long journey. I'd encourage you to consider signing up, because the various modules have exercises that help you begin to develop each part of your voice.