How to track IP address of anyone using email?

How to track IP address?

step 1:
know what is your victim email id.
For eg:
victimid[@]gmail.com
step 2:
Register an account here: http://www.readnotify.comstep 3:
send mail to victim using your readnotify.com mail account. Before sending mail append ".readnotify.com" at end of victim mail ID. 
For eg:
victimid[@]gmail.com.readnotify.com 

step 4:
if victim opens the mail, his info will be tracked(IP address) and mailed to your account.