Drawing tools are useful for creating borders, lines, graphs, or other artistic effects. Sans Serif fonts in no more than two or three sizes and styles throughout are easiest to read. Hyphenation and fancy script can distract the audience from your message. The font should be large enough to be readable by the audience in the back of the room. Use the page break feature between each slide.
Color can be a great enhancement but don t use all the colors of the rainbow.
Limit colors to three, one for background and no more than two for headings and text. High contrast and change are attention getters. I have found that a blue background with black text and bright yellow for underlining, borders or boxes works well in most lighting situations. Avoid combinations such as green and red that are generally hard to read Graphics and pictures can add class, but should not clash. Use them sparingly to avoid clutter or distracting the audience.