There are a lot of resources on the Highland Utah Stake website I've posted at the bottom that you can go to for more information, and I encourage you to do so, but for the basics on what to store and how to use it, watch the video here about Sanitation for an Emergency.
You'll learn how to convert your toilet to a "dry toilet", how to dispose of the waste properly, and some things to store in a portable sanitation kit.
For more information, go to the Highland Utah Stake Website You will find info on everything from how to build an outhouse to how to make your own laundry soap. Check it out!
Popular links:
Sanitation Workshop
Sanitary Napkins Pattern
Flannel Cloth
A Years Worth Of Laundry Soap for under $30