On the top right hand of your dash board, you will see an icon with a silhouetted face (or your own picture if you have changed it) with an arrow pointing down next to it.
Upon clicking on the arrow, a drop down list will appear with the options Profile, Upgrade your plan, and Settings.
Click on the Profile Option.
If you scroll down to the bottom, you will see some red text which writes:
"Change your Password"