If you are on a phone that has Force Account Code enabled, and if you are a student with an NFTS phone you will be, the procedure is as follows:
Dial the number you wish to call, with no prefacing numbers, so no "9" for an outside line needed.
The phone display will read "Enter Account Number".
Type the account number you have been assigned, such as 3333 and then a hash. For instance, 3333#
The phone will then dial out. Account codes are only required for calls outside the NFTS.