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It is probably easiest to copy & paste a graph or chart from Excel, but what if you have a picture to add? The following steps will walk you though that process.
Click on the Insert tab on the ribbon.
Click on the Picture button and navigate to where you have the picture - select it an click Open.
The item is now added to your poster -- but you will need to adjust the size of it and its location.
Aligning objects can be done so that the tops are inline, or align boxes around the center of a column, or align it with the left or right side. You will become very familiar with doing this.
Select the objects you want to align - perhaps the heading across the top of the poster - by clicking on one and then holding down the Control key before clicking on the second object. Note: layered boxes behind text need to be selected too.
Click on the Drawing Tools tab (on the Home Ribbon) at the very top of the screen and look in the Arrange group for the Align options - use the drop-down arrow to see all the options and select the one you need.
The boxes will move according to the alignment you specified.
Moving Objects with More Precision
Objects that are selected can be moved with the 4-arrowed cursor, but it may not have the precision you need. A combination of keystrokes can help increase the precision of the move.
Select the object(s) - so that it is moveable (solid line) and not ready for you to add more text (dashed line).
Simple small nudge: Hold Alt and use the mouse to move a box or image in very small incriments
Keyboard shortcuts with the Shift, Control, or Alt keys. Hold one of them down and use the arrow keys on the keyboard to:
Shift = resize the box
Control = nudge the box up, down, or to the side.
Alt = rotate object (only the left & right arrow keys work with this one).