Fonts without serifs like Arial or Lydian are preferred to fonts with serifs like Times New Roman. The latter are better 'seen' in printed material rather than 'slides'. A size of between 28 and 44 points are used for presentations in average sized hall seating less than 300 people. It is advisable have only six lines to each slide and about six words in each line. The special effects that a computer can give include transitions, build effects and added sounds.
Transitions are the way the computer changes over from one slide to the next.
Several effects are available. We prefer to use only 2 to 3 types of transition in each presentation. The random choice is to be avoided as the computer can randomly assign an inappropriate transition to a slide. Build effects are the way each 'object' of the slide appears. These objects may be a graphic, a circle or a rectangle round a point the speaker wants to highlight or the way different lines in a bulleted list appear.