Take this scenario.
We want the laptops on vlan 100 and the PCs on vlan 200. We don't want communication between vlans. Here is how it would go, assuming the wds link is configured and working.
1. create the vlan interfaces
add name=vl-laptops-wds1 vlan-id=100 interface=wds1 disabled=no
add name=vl-pc-wds1 vlan-id=200 interface=wds1 disabled=no
Note that the name of the vlan interfaces can be what you like, but you should make it something that makes sense. I usually name mine in the above convention - vl for VLAN, followed by the name / use of the vlan, followed by the physical interface.
2. create the bridges and add the vlans
/interface bridge port
add interface=vl-laptops-wds1 bridge=laptops
add interface=vl-pc-wds1 bridge=pcs
Note: leave the physical interface out of any bridges (in this case wds1)
3. add the ether interfaces to the appropriate vlans. In this scenario, E1 to laptop vlan and E2 for PCs
add interface=ether1 bridge=laptops
add interface=ether2 bridge=pcs
Thats it! you have both vlans being tagged over the wds link. Happy vlanning.