For PCCW (netvigator) user, their wifi have two type:
If your netvigator board-band internet included signal device WIFI, you will receive a activation code though SMS, the code should come in 7 digits. When you find the PCCW SSID, you will direct to a landing page. Scroll down to the bottom and you will find the Signal Device Activation, and then input your activation code and a name and then click activate. After that, PCCW will remember your device's MAC address, so you have to call the Hotline to release it if you you want to switch device. Don't login in with your login ID because you will get charge with $3/10 min.
The other one is the plan included USB modem, you have to do the login with your SIM number and password on the landing page, so the wifi will be free. Same as above, if you login with your netvigator ID, you will be charged with $3/10 min.