Migrating from one Macbook to another
You can use builtin Time Machine application.
First - make a backup on Your external drive using TimeMachine.
Then on the new Mac use Migration Assistant.

Here is the link with detailed info: http://www.macworld.com/article/2066996/how-to-transfer-backups-from-time-machine-to-a-new-mac.html 


  On the new iMac make sure that you have access to the drive where the Time Machine backup is stored and then launch Migration Assistant. It will notify you that it needs to quit all open applications. Allow it to do so.
  The first Migration Assistant screen will offer three options regarding data transfer. Select the first one, which reads From a Mac, Time Machine backup, or startup disk and click Continue.
  In the next screen choose the drive that holds your backup and then click Continue.