Being great believers in creative freedom, we consider un-required alignment of slide objects (such as shapes) probably as bad a design decision as aligning nothing at all. In the end, every decision to align needs to stem from your creative thoughts — sometimes it works, and at other times, an unaligned bunch of shapes looks perfectly natural and organic. Also, remember that alignment works with more than just shapes — and you can also combine shapes with other slide objects and align them all together.
Learn how to align shapes in PowerPoint 2011 for Mac.

