If you don't have the resource to train internally and have to rely on the vendor make sure they understand the users they're training and impress the importance of both relevancy and time management to them.
Subject to suitable resource, the training policy you should apply is what's commonly known as the train the trainer approach. This is the most economical way to train your staff. The software vendor will train a number of super users within your organisation and they in turn will train the remainder of the staff.
However, beware of creating too big a training chain between the external trainer and the end user. The more people the knowledge has to pass through to get to the end user the more it can become diluted and subject to Chinese whispers. You don't want a key feature to be lost in the relay.
For your training to be successful it should be
Standard user manuals can be inaccessible to your users because they contain too much that is not relevant and not enough detail about how they specifically do their jobs.
Devising your own manual can be very simple. Walk through the process on the system taking screen shots and adding text. Each time the screen changes take a snapshot by pressing the Alt key along with the PrtSc key on your keyboard. Then go to your word application and press the Ctrl key along with the letter V on your keyboard. This retrieves the screen image into your word document.
User manuals should be controlled with the same rigour as your Quality manual as they can equally go out of date.
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