I use post it notes quite often. They are much better than staples or paper clips to identify/label something. If I use them in the refrigerator or freezer I add tape to the bottom so that is doesn't get lost. I prefer a light colored note because it is easier to read. The colored ones are prettier but I prefer light yellow.
Don't know how we ever got along without them! They're a great way to perk my memory for important revisions to be reviewed later. It gets the job done and is very economical.