I'm assuming that there isn't another switch connected to the UC540. If so, you should be able to simply connect the expansion port of the
UC540 to the 2960. Make sure that the 2960 port is set up as a trunk port, and that you are using vlan 1 as the VLAN that the PCs should connect to. If the VLAN on the 2960 is not VLAN 1, then it is still reasonably straightforward, but there are a couple of extra steps. Likewise if the expansion port on the UC540 is already in use, you can use a different port, but you will need to change the smartports role for that port from Desktop+IP Phone to Switch.
Cheers,
Dave.