A simple trunk port would look like this is all three a tagged vlans.
---setup trunk port
set interfaces ge-0/0/0 description "trunk to AP"
set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
---create the vlans
set vlans ssid1 vlan-id 10
set vlans ssid1 interface ge-0/0/0.0
set vlans ssid1 vlan-id 20
set vlans ssid1 interface ge-0/0/0.0
set vlans ssid1 vlan-id 30
set vlans ssid1 interface ge-0/0/0.0
If you also have an untagged mgmt vlan
--the vlan setup does not include the trunk port but will be used by access ports that are on this same vlan
set vlans mgmtvlan vlan-id 40
--add the vlan tag as "native" untagged to the trunk port
set interfaces ge-0/0/0 unit 0 family ethernet-switching native-vlan-id 40
---client untagged access ports
--create the access port
set interfaces ge-0/0/1 description "my client"
set interfaces ge-0/0/1 unit 0 family ethernet-switching
---assign to the desired vlan
set vlans ssid1 interface ge-0/0/1.0