I happen to think it's great fun to decorate our 13' Scamp
according to my whims and frequently change the look depending on our destination. My photo shows the curtain panels and pillows for our Southwest trip. Personally, I think too much print in a small space is overwhelming. That's why I have chosen to keep the original cream-colored curtains and added my custom curtain panels. The cream panels let in the sunshine and keep out curious eyes.
Typically, sewing curtains is a simple project as it is simply a rectangle using only straight lines of stitching. I believe that all you need is the specialized tape that is used in your camper/trailer. Many websites sell this item. Also, you can find ideas for curtains by simply entering the words "sew curtains for casita" in Google. If you are not handy with sewing you could ask a friend to sew for you or even the folks who do alterations at your cleaners could easily do this job. While you're at it, make matching pillows!
I found one website that suggests keeping the blinds that come with the Casita
and making a decorative valance that requires no sewing! Mrs. Padilly's Travels ยป Window Treatments for my Casita Travel Trailer
Because I have a Scamp
which came with curtain rods, which I love, I cannot answer your question specifically. Other members, however, have answered your question in various ways. Go to the "Search" button at the top of the FGRV forum page and scroll down to the bottom. In the "Search Site/Google" section write the words "curtain rod Casita" and BOOM you will have answers galore. If you want to ask members for details you could "PM" (private message) them. Here is one answer, among many, that I found. How I did the curtains in our Casita
Also, there is a Casita forum online where you can ask this question.
If you should have questions about making curtains/shades I will be more than happy to assist you just PM (private message) me.