Question : How to get google+ client id and client secret?

Answer :

1. First go to google developer console https://console.developers.google.com/apis/
2. If no project is created then create one and select that
3. Then enble google+ api from the api list first
4. Then from Credential menu > Create create credential select OAuth client id
5. Then fill the information like below
6. Then copy the client id and secret

Make sure that you set javascript origins and authorized redirect url perfectly. Also newly create alient id and client secret need some time to be activated. So wait atleast 5 min after creation.