This is very very common error on android.So don’t panic when you see this for the first time.
First of all, clear the cache and reboot the phone. If it fails follow the below method.
1. Go to settings>applications>
2. Select Play Store.
3. Click the button ‘clear data’.
4. Go to settings>applications>
5. Select Play Store Services.
6. Click ‘clear data’
Now open the Play Store again, it will ask to select the gmail account.
It works perfectly!!