Extending a WiFi network

[#1]

I was handed a ZyWel NWA-1100 wireless access point, the person that gave it to me said 'it should extend your wireless network'.
Considering I have an existing WiFi network, I want to extend the exisiting WiFi to cover a larger area, by picking up the existing WiFi signal and rebroadcasting it
I'm stuck on the first page do I configure in:-
Access point mode,
Wireless Client Mode,
Ap + Bridge mode or
Bridge Mode.

[#2]

trial and error ............... Ap + Bridge mode

[#3]

I'd say either AP+Bridge, or just Bridge.
Remember to find out what channel your original wifi is on, and set the new AP to the same.  Also ensure the same security settings are set, and the same password also.
Sounds obvious, but I'd have missed it.
Good luck.  It seemed like magic when I set one up, but I can also imagine if it hadn't have worked, I'd have been at a loss as to what to do.