More information is available at the community portal. You may ask questions at the help desk, village pump or on IRC channel #wikimedia-commons (webchat). You can also contact an administrator on their talk page. If you have a specific copyright question, ask at the copyright village pump.
-- 20:33, 19 October 2011 (UTC)
You ask at the Village Pump how to add categories to images. Let's look at your image File:Mountain Lady's Slipper 1 (Cypripedium montanum).jpg. If you click the edit button at top, it will show the image description's wiki code. At the bottom are brackets with "Category:xxxx" in them. For this image, you'll see
[[Category:Cypripedium montanum]]. Any time you want to add a category to an image, just follow that example ... the name of the category is what goes inside the brackets on the image page. I'm assuming you know (at least basically) how to navigate the category system on Commons; if you need more help, or ever have a question about anything on Commons, leave a note on my talk page and I'll help however I can. Cheers! — Huntster (t @ c) 06:13, 24 October 2011 (UTC)
Thank you so much for taking the time to explain that - it's exactly the step-by-step instructions that I needed.