Video 1. Make sure your words and graphics are in harmony
In this video below John shows how a typeface can express an unintentional message. Now, the "after" example does not mean that it is the best solution possible, but it is a big improvement and serves to illustrate what a difference shapes (from sharp to soft) can make. Personally, I do not have a problem with the color red for the tooth as the tooth is actually white taking up the negative space (though John does raise a good point). Additionally, red has good contrast with the blues and red & white are also a symbol of help or medical care such as in the Red Cross association, etc.
Video 2. Working in a tiny space: Think simple
John's point in the video below about choosing simpler and more focused images is especially important for websites but the concept is applicable to presentation visuals as well. A common problem in presentation graphics are designs which have too many elements and lack a clear focal point. A good photography tip as well is to try to compose your shots in a way that eliminates unnecessary detail or clutter.
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