You will first need to create a Lock Screen password.
In the Settings menu, select the Device Tab. Then tap Lock Screen. Then tap Screen Security. From here you will select either a pattern, pin number, or password.
After entering the pattern, pin number, or password twice, it will be successfully saved. This will now be the way you unlock you device.
Next, navigate to the General tab within your Settings and select Users. Tab the Add User button and choose Restricted Profile from the Add User menu.
A New Restricted Account will be created. It will automatically open to a screen where you can select what are Allowed Applications. A check mark next to the Application will show that it is allowed and available to the user. You can also tap on the User Name (or photo) to rename the Restricted User.
After you have selected which Apps will be allowed, tap the Users option again to show the saved Restricted User.
This Restricted User can now be selected from the start screen when you turn on your device or bring it back from sleep mode.