What do I need to do to get this kit?
This could help: https://zwiftjerseys.com/the-herd-riders-club/
Does not look like a similar jersey(what I can see) and not a complete kit as on my pictures.
You can get it by doing one the herd group rides.
Look for a Herd Ride in the companion app that has #jerseyunlock in the description. You need to ride the entire 60 minutes of the ride and it will be in your garage afterwards. IIRC you don’t get a notice that it’s been awarded but it will be in your garage.
Thanks for the information!
Herd Ride next week will be my goal 
HERD Kit is 