Sure - you need to configure it on your clients/servers (known as supplicants in 802.1x language), on your switch (the "authenticator") and on your ACS server.
Depending on the supplicant software (native Windows or AnyConnect client Network Access Module) the instructions vary but are pretty self explanatory - just provide credentials when prompted.
The switch piece is explained in the IOS configuration guide for you platform. For instance, here is a link for a typical switch (3750-X and 3560-X).
Finally, the ACS server setup is explained here. The example is for a Lightweight AP connecting to a switch but the concept and server side setup is pretty much the same.
