Open Google+, pull the menu out (tap on the top left G+ icon), select Location Sharing then turn location sharing on. From there you will have options below to see who can see your location and at what level of precision they can see you at. This is a good time to update your Circles to enable who can see where you are at.
Go back into the menu options and select Locations and you'll be taken to a map and can see the location of anyone in your Circles who has publicly shared their location with you.
That should do it. Let me know if you have further questions.