I read somewhere recently (can't remember where) that you should interleaf them with acid-free paper and put in an acid-free box. The problem is that this is kind of expensive.
If they were mine, I would scan the parts I was most interested in into the computer, as there are a lot of adjustments you can make to improve them once they're in your computer, i.e.get rid of yellow. I did this with a family clipping that had been sitting around for about 60 years and was very yellow; it looks very good now.