On-screen help, in the form of pop-up messages or an easy-to-use help feature, will help a user learn about the interface more quickly. These messages will need to be helpful and assist a user to easily correct their errors or to learn how to complete an unfamiliar task.

Error messages can be helpful and unhelpful. The helpful messages will help a user to correct the error they have made, so increasing the speed with which they learn to use the interface. If a user was given the unhelpful message, it would not help them continue with their task (although it might help the programmer who created the system).

A designer must try to ensure that the actions required to use the interface are held in a user's short-term memory. This can be achieved through the use of a consistent and uncluttered page layout.

As far as possible a designer should consider the pre-existing knowledge of the user. It may be that the user is already familiar with the interface and is simply using screens that they do not often use. If this is the case, then a designer must ensure that the user's existing knowledge will enable them to use the less familiar screens.

As the user moves through the interface  from page to page they will be making use of their short-term memory. If the designer has considered, and used, consistency between screens, then this will help the recall of the skills and knowledge required to effectively use the interface. This in turn, will increase the speed at which the user learns to use the interface.

The most important information on the screen needs to be obvious with the screens clearly labelled. Any area where data/information has to be inserted by the user also needs to be clearly labelled. The use of pop-up messages could also help keep a user's attention.

A designer could also use flashing graphics, sounds or pop-up messages to draw a user's attention to an action on the screen. These features should, however, be used sparingly as too many features can detract from the use of the screen. A user's attention span can become shorter if there are many features on a screen. Similarly, if the screen is permanently filled with, for example, flashing graphics, a user could become confused and feel uncomfortable with the screen.

Most screens will include some menus and sub-menus to help the user complete tasks. These menus should remain, as far as possible, consistent. The menus should be in the same place on the screen, and the words used should mean the same on each screen. In addition, if sub-menus are used, then these should relate to the same words on each screen and again be consistent. If graphics are used to denote a task, for example a pair of scissors to denote the action 'cut', then the graphic for this action must always be the same.

The screens will also need to have a consistent layout. If the user has to search for information on each screen, then the attention span will decrease.

Screens should also be designed with a consistent colour scheme (which might link to the corporate style of the organisation for which the interface is being designed).

These common perceptions should be considered by the designer. If a user feels comfortable with the interface then, theoretically, their confidence with the interface will increase.

In addition to a user's perception of the colours used in the user interface, the use of sounds is also important. Users can perceive sounds as being happy or sad. This ould relate to a sound that indicates a positive response or a negative response.

If a user hears a sad sound, then their perception will be that they have done something incorrectly or even that they cannot correctly use the system. Conversely, when a user hears a happy sound, then their perception will be that they have done something right and that they are using the system correctly.