Switch to Lightning Experience

Once Lightning Experience is enabled and permission assigned, click on Switch to Lightning Experience after clicking on your name, as seen in the following screenshot:

Here is a screenshot of the modern Salesforce Lightning Experience:

Notice that the user interfaces of the Classic and Lightning Experience are totally different; if you still see a bluish background around the tab menu, you are in the Classic interface. Follow the Let's turn the Lightning Experience on section to enable it, or contact your system administrator to enable this for you.

As of now, not all features from Classic are available in Lightning Experience; you may need to switch back to Classic when needed. For example, Recycle Bin is not available in Lighting Experience. To switch back to Classic, click on your photo, then click on Switch to Salesforce Classic. You can use the same path to switch back to Lightning Experience: