HyperV + pfSense VLAN's on one vNic

[Rexima]

I can't figured it out, how to run on one vSwitch/vNic many VLAN's to manage networking?

Quick explain:
I have one VSwitch which is called "VM" and i want to run two seperated networks on it.
One for my virtual machines, and the other for my friends vms.

And i want to add in the future, dynamicaly more networks to this vSwitch/vNic.

Or should i setup for every new network a new vSwitch?
If it's so, i have a huge problem, because i can't/wont have any downtime.
If i need to add a new vNic to the vm, than i need to stop it, and i will have problems than.

(Sorry for my bad english, its not my native language)