I saw these salads in a magazine recently and thought wow, those are pretty. But it didn't occur to me that they are also very functional. Between dressing my salads before leaving the house in the morning (soggy) and including the dressing in a sandwich bag (messy) I don't really have a good method for transporting it. But by layering the ingredients (with the heaviest, least permeable ingredients on the bottom) you can prevent the salad from getting soggy. Also, by simply shaking the jar to distribute the dressing you avoid a mess (and have nothing to throw away.)
If you have a wide mouthed jar you can eat right out of the jar. For narrower jars like the spaghetti sauce jar pictured just shake, then dump into a bowl.
If you're not taking a picture the label doesn't really matter. But to remove it soak the jar in hot water then use isopropyl (rubbing alcohol or nail polish remover) to remove the residue.
Here is one recipe that worked particularly well....
Champagne Vinaigrette (Trader Joes)
Layer the ingredients in that order and you're good to go!