I have talked about the header and the footer and how they build a natural frame for your presentation. But guess what? You need a second frame, an invisible inner frame. You need it because there is nothing worse than text or objects that are almost touching (or even touching, god beware!) the header or the page margins. To avoid this, you have to make sure that there is a minimum distance between anything you put on your slides and the header and the footer as well as the left and right edge of the slide. So please, create some invisible upper and lower borders right below/above the header and the footer and also invisible borders on the left and right margin. By doing this, you create the frame that you are allowed to fill and make sure that there is some white space between your content and the header/footer and the page margins respectively . The easiest way to create such an invisible frame is doing a right mouse-click anywhere on the slide. Then select “grid and guides”, then “guides”. You can now move those guidelines with the left mouse-button and use them to create a frame of reference for all your texts and objects. Use the ruler function (also by doing a right mouse-click anywhere on the slide) to make sure the guidelines are balanced.
Check the following example: