|Detailed make/model info on the router would have helped. Assuming it's a SOHO Router and set to it's defaults:|
Connect the highspeed modem to the WAN port of your router.
If your IP is static then manually configure the TCP/IP settings on the WAN port as per the info supplied by your ISP.
Leave the LAN side of the router setup with the default settings.
Most SOHO Router's use the private Class C subnet. All the ones I've worked with use either 192.168.0.0/24 or 192.168.1.0/24
Connect a computer to a LAN port of the router that is set to DHCP and allow the router to give it it's TCP/IP settings. Confirm you have internet connectivity. Once your SOHO Router is setup and working properly confirm the DHCP Server settings on the router. What you want to know is the scope. Typically the default on a SOHO Router is 100 to 200, keep this info in mind for setting up the switch.
Connect the switch to a LAN port on the SOHO Router and connect to it's management port with a console cable. You'll have to configure the switch. Give it an IP in the subnet of the LAN side of the SOHO Router but ensure you use one that's outside of the DHCP Scope so as to avoid duplicate IP errors.
Once the switch is configured test to ensure it's working properly and clients plugged in to it get LAN and internet connectivity.
Last, configure the Access Point with an IP in the same Subnet as the switch but also outside of the DHCP scope. Plug it in to a port on the 2960 and test to ensure the WLAN is working properly.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.