Migration Assistant
Do you need a special cable to use Migration Assistant? Connection details says “null” for both ends.
iMac, OS X 10.11
Assuming you're using a Time Machine backup, all you need to do is attach your Time Machine backup to your Mac with the cable you've been using to create the backups.
If no backup, I strongly suggest you create one on a dedicated HDD.
Are you wanting to attached to a different device?