The FAQ here provide all the needed info on saving and how to store your seeds. I have linked it below for you.

Dave

Here is a link that might be useful: Seed Saving FAQ

Canna lilys are stored by the roots ( bulbs). If you are in a colder region, they must be lifted before frost, and the greenery allowed to die off, and then cut off. You then clean the bulb and put it in sawdust or peat moss etc and store in a dry cool place for the winter.

Here is a link that might be useful: organic gardening.

I am planing on storing my seeds in either the little plastic baggies or some homemade envie that I have learned to make and these will be all be stored together in a extra photo box that I had on hand and then they will be kept in the unheated basement until it is time to winter sow them.

But everything I have read says to store in a cool dry unheated basement or garage. But not too cold to where there is a chance of freezing.

Paula

I store mine at room temperature in any kind of packet after drying.

Canna have a very thick seed coat. Don't forget to nick and soak before planting.
The thickness of teh seedcoat has allowed canna to germinate successfully after being found 100's of years later! They were even rumored to germinate after being found in Eygptian tombs! That claim is false according to the web, but they have been able to germinate from very old seed.

You'll do fine.
Karen