Let me clue you in on something: nobody cares. What matters to your boss is that you know within 20% accuracy (not exceeding budget) how much money you'll need to complete your project and when you'll have it completed by. Your resources will take one good look at your diagrams, turn it upside down, move it closer to their eyes, pull it away from their eyes, throw up all over it, drop it, stomp on it, and pray they never have to look at it again.
Your team just needs to know what you expect of them (based on what they told you they needed during the project scoping/estimating phase), when you expect it by, who their backup is, and then they just want to be left alone to do their job.
So if you absolutely must use a diagram, here are a few cool ones I found that don't make me want to quit my job and become a gardener from some rich old people on the East Coast. Enjoy!
Image Source: http://www.waterstons.com/Service/Project+Management/
Image Source: http://themindproject.com/tag/funny/
Image Source: http://www.mpmm.com/project-management-methodology.php
See you real soon!