How Can I Maintain Appropriate Formality In The Presentations?

Your first question should always be: How formal do I want to be on this specific occasion. A formal tone results from visual aids created entirely in advance before the presentation starts. If the occasion is formal you may use slides overhead transparencies, flip charts.

The important variable is your having prepared them in advance. Formal aids may be produced by professional artists or by computers and often in many colors. They assure you of a great deal of control over your presentations time and content. At the same time you give up the chance to include your audience's comments.

A semiformal tone comes from creating your aids partially in advance and partially during the presentation. For example you might prepear part of a chart and then for more dramatic effect writes certain numbers as you speak. Or you might have blanks that you will fill with audience responses.

A semiformal tone allows you to maintain some control with some flexibility and spontaneity. Finally if you wan to establish a more informal tone, create your visuals during the presentations itself. You might for example choose to write on blackboard, a flip chart or even an overhead transparency during the talk.