You should use a pressure canner not a pressure cooker. This is the brand you will see used the most. This is what we used for canning tuna in San Diego.
http://www.allamericancanner.com/allamericanpressurecanner.htm

If you are doing a lot of canning the 941 is the one to get. It cuts down on the number of times you have to cook. A smaller one does just fine but you are going to spend more time cooking in smaller batches. They last forever and you can can anything, including salmon.
If you want detailed instructions, send me a PM and I'll send you a link to a So Cal website with step by step and pictures.