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Backgrounds: Putting a Shape Behind Text or Objects
Make sure text is formatted.
Click "Insert" tab and then Shapes to choose the shape. You will probably choose a rectangle -- look below the first group to see all of the rectangle options.
The pointer changes to a cross-hair and draw your rectangle over the desired box of text or heading starting at the top left corner and draging it to the bottom right corner.
A solid box of color will appear over your text box with the little selection marks still in place.
Click on the new "Drawing Tools" tab and in the group of arrange tools, click on Send Backwards.
You will now see your text with a colored background.
The box is still selected, so you can continue to adjust it: -- resize the box, if needed, -- change the color (see the Shape Fill icon on the Drawing Tools tab), -- adjust the transparency - lower or higher.
To change the color to a gradient look, right click on it to bring up the menu options and click on Format Shape. Choose Gradient Fill and adjust settings as desired.
Backgrounds: Adding a Colorful Background
To include a colored background or an image that covers the entire slide, follow the steps below.
Right click the slide and in the pop-up menu, choose Fomat Background.
Option #1: Choose from the designs Microsoft has for you - click on the Design Tab and hover over the designs in the Themes group to see how it will look with your poster.
Option #2: Follow the instructions to the left for inserting a colored box behind text - except you will draw it from the top left corner of the slide to the bottom right corner of the slide. Then use the Arrange option "Send to Back" instead of Send Backwards.
Option #3: Insert an image, just like a colored box. Be very cautious with this option. Some images do not scale well on a poster and most images will conflict with the readability of your text. If you do insert an image, be sure to adjust the transparency.
Backgrounds: Adding Color Behind Headings
To have greater flexibility with headings, have them in a box separate from the text.
Follow instructions to the left for adding color behind the box.
Unlike the text, you can use create a good impact with a dark background and lighter colored font.
Make sure the corner style of the colored rectangle is complementary or the same as the text box - it should have a cohesive look throughout.