One of my pet peeves is Cisco switch and router interfaces that remain unlabeled. There is nothing worse that trying to debug a network problem when the problematic interface is unlabeled. Instead of spending valuable time working on the actual problem, you've got to trace down where this cable goes and what it plugs into.

So, my challenge to you is to always set the interface description. This can be easily done with the description interface configuration command. What to put in the description is up to your personal style (or policy, if such exists), but I recommend including the name and port of the device on the other end of the connection. In the case of a leased circuit, it's also helpful to include the provider, circuit id, and account number.

For example, a switch port that connects to another switch might look like this:

Switch1#config t
Switch1(config)#interface GigabitEthernet0/1
Switch1(config-if)#description Switch2 Gi0/3
Switch1(config-if)#end
Switch1#show interface description
Interface                      Status         Protocol Description
Vl1                            up             up       
Gi0/1                          up             up       Switch2 Gi0/3
Switch1#