How to help develop your speaking voice

Much of what we do is technical, but how we communicate and present that in a meaningful, impactful way is important.  My university hosted a toastmaster's workshop to help us better communicate our science, which helped me tremendously in how I approach and convey information.  

The Toastmasters is a nonprofit educational organization with the goal to help you express yourself better with clubs around the world (and virtual).  You can "practice the skills you need to communicate with confidence and excellence. It all starts with a fun club environment where you will learn and practice together—to grow individually."