set up email service for wordpress
install plugin Postman SMTP
go to settings -> Postman SMTP
follow the instructions,
input the email you want to use as admin account of the site
it will automatically detect which email service you are using, e.g. I use google gmail,
it will suggest the SMTP port, and OAuth 2.0 for authentication
redirecting to https://www.google.com/accounts/Logout?continue=https://console.developers.google.com/start/api?id=gmail
register for google API,
register for Authorized JavaScript origins, and Authorized redirect URI in google’s API page
get back
Final step, you should grant permission with google
http://jishichao.com/wp-admin/admin-post.php?action=postman/requestOauthGrant
Then you have everything.