Connecting Apple Watch to Zwift

It is still a bit hit and miss (unlike my Garmin, which connects over Bluetooth flawlessly , not via ANT+ as I erroneously said in this video).
Still I am persevering.
Actual sequence IMHO should be
Start Indoor Bicycle trainer, in my case TACX
Start Zwift App (in my case on an Apple laptop)
Start Zwift Companion on iPhone. Obviously bluetooth is switched on
Start Zwift app on Apple Watch
The Phone app should link to Watch and Pair
On Zwift app on laptop goto Heart Rate and Search
Apple Heart rate should appear