I always try to make the label before I plant. Then after planting, the label can go in the ground right next to it.
If I am planting more than a couple, I keep a piece of paper with me to write down the location of the daylily in my garden. Then go back to the computer to mark it on my map. Here is one section of my garden where I have the daylilies circled in red. It is something that absolutely must be done after planting or I will forget to update the map! I also have a legend with all the names of the daylilies and their location. May be overkill, but I am always afraid my plant stakes are going to get ruined or taken.