[DF Simmons]

I could use a general roadmap to help me with the following situation which I seem to encounter about once every 4-6 months (just infrequently enough that I subsequently forget how to bet configure a solution).
Pre-existing four port wired/wireless router connected to the internet via a Comcast cable modem. Router relocated to a remote location of home (e.g. basement) in order to de-clutter desk and to establish a wired network. Wireless connectivity now not so good on 2nd floor so a WAP is added up topside.

Seems like I can muddle my way through this but not usually without a call to either Comcast, the manufacturer of the pre-existed wired/wireless router or manufacurer of the WAP (been using the Netgear WG602).
I know to turn off the wireless side of the router. Just not sure of how to configure the WAP so it is talking to the modem. And other than turning off the wireless in the router are there other potential issues of compatibility between the router and the WAP?

Perhaps...probably there are already several posts relating to this situation. A link would be helpful.

Thanks in advance.

doug