If you scroll to the top of this page, you will see the "search" box. Type in "plant tags", and you will get tons of ideas for making tags, and lots more ideas on different "store-bought" ones. You can also make a "garden map" to help keep track, and, a "logbook" can be a big help to keep track of not only what you have, but where you got it, and when! I ,myself, use metal tags, wired to a long nail, and pushed into the soil at the base of the iris, as well as metal "rose labels"( I think PawPaw is the brand, and if you google rose labels you'll see a bunch of styles) that I put out in the spring ,and remove after bloom is done. I also keep "log books" with the cultivar name, hybridizer, etc. ,and where and when I got it, and it's bed location( south side of house,west side of driveway, etc.)....but, I'm an iris addict, and can't help myself!
have fun !...Arlyn