You can simply follow these steps:

In the Settings/Preferences dialog (Ctrl+Alt+S), click Editor | General | Auto Import.
In the Python section, configure automatic imports:
Select Show import popup to automatically display an import popup when tying the name of a class that lacks an import statement.Select one of the Preferred import style options to define the way an import statement to be generated.

Let me know how it goes!
Anyone know how to actually enable auto imports? I've tried in the pref's auto-import settings, cleared my project cache and restarted but I never get any auto import prompts!
On mac, running latest pyCharm CE version.
this is not simply a matter of enabling the setting; that setting is enabled in the preferences but still I get no suggestions for auto-imports
ie
import requests
gets me nothing no popup, no suggestion to import it etc.
Enable PYCharm auto-Imports for python