Last week, I stocked up on some olive oil, shortening and canola oil for my storage. I had to squint to see the recommended expiration dates on the bottles, so I rewrote those dates on the bottles with my marker. Doing this makes it much easier to pick the bottle with the closest expiration date, especially when I'm in a hurry.
You can get permanent-ink markers in many different colors. If you were really ambitious, you could color code purchase and expiration dates. You could also color code products based on contents. Click here for a previous post with more ideas for labeling home storage.