Here's how to enable the lightning experience for your users if you haven't already:
- Click Setup
- For the first few months of this change, the Lightning Experience link is on the upper right. However, I'm assuming this will drop lower into "User Interface" or something like that later.
- Click the link
- This page shows some videos as well as some text about the experience and its intentions.
- At the bottom you have the options of which pieces you will enable for your users. The last item is the most important.
- After this is enabled, each user will have to change the setting themselves to deploy it. This is done under their name (at the top), clicking <NAME>->Switch To Lightning Experience