We do what Mfecko does plus make up a one-page cheat sheet in Word that is customized to the customer. Every user application is different. A user that has direct trunk keys vs call keys, park keys, etc, all so different that a standard guide doesn't cut it.

It takes a lot less time to type something up each time then it does to do more on-site training.

Most 'factory' user guides are confusing and worthless and should only be used to supplement a custom guide.

The attention span of a user is usually about three minutes at best, so a one-page user guide is about all that will work. Skip all the fluff features and get right down to the brass tax of answering/transferring calls.