This tutorial has been updated here http://blog.nem.io/how-to-use-multi-signature-accounts/
Here is a video in addition to the more detailed instructions below. [url=https://www.youtube.com/watch?v=Jd-ZIbiFuOg]https://www.youtube.com/watch?v=Jd-ZIbiFuOg
Old wallets and passwords from previous versions of NEM prior to 0.5.4 should be discarded. They won't work well with this update. If you have any problems getting NEM started, please read here for more information about trouble shooting. https://forum.ournem.com/beta-launch-discussion/nem-beta-0-5-4/
Once you log in, you can see the name of your wallet in the top right hand corner. Your actual account (seen on the top left side) does not have a label yet, you can create one if you wish by going into Address Book. It is not necessary to label an account, but I like to do so for clarity.
To label an account in the address book, copy the account number, click on Address Book, and then click
Awesome guide, thanks! This should help the uninitiated get started with multisig. 
Thanks!
And thanks to Mixmaster for helping me clear up some points. ;D
nice work!
nice job jabo, great tutorial
great tutorial, time well invested.
Great work Jeff…even I understood it…lol…so it must be good…
that is a new function. I am not sure why it does that