I have never made a curtain/drape with the print on both sides.

Does this fabric have a print on it that has a "top" and a "bottom"? For example, animals, trees, flowers or whatever...so that if you fold it over, one side of your panel will show the picture/print right side up & the other side upside down? Not sure I explained that very well.

Yes, there is a side of it also, I guess I should cut then be careful to sew together it so the palm trees won't be upside down. It just the back side of this fabric is really ugly looking. And I wanted like maybe two curtains? But then I need to install a second rod for the outer and inner curtains, and I wanted them thick to block light when sleeping.

If you are trying to hide the back side of the print, you could use a plain white fabric as a liner. If you line it with the same fabric, when the light shines in, the outside print may show through and be visible in the room.

But it's a super thick fabric, I will try testing it up to the light and I will snap a photo later on today. I think I lining would make it even thicker? Unless I have a second rob set up for a lining for a double curtain?

I can't see light through it at the window. Here is the photo of front and back side, you can see how ugly the back side is.

compared to the front. Wow, this site takes a big photo, but when I mouse over it enlarges it. I did not even reduce it a little bit. The selvage has a copyright so I thought I would add it to the photo, so it would be still copyright. Anyway, it's black out fabric Palm Tree Light blocking curtains.

I got an idea! I could sew a black lining on the back instead of a white one. The wrong side would not be ugly if it was all black instead of oddly white. It's too bad, I don't know how to sew linings. I have to look that up again.

You also want to consider how this window treatment will look from the outside.
If you walk outside your house and look at this window, what will look pleasing to you...a white lining, a black lining?

At my home, the windows that have lined drapery are all ivory lining.

The house is painted blue so it is a dilemma. I was thinking black would be better, but I guess I will hold up samples on the outside to see. I just so wish I could have palm trees on front and back somehow, but the windows has bars on it, so it is not so pretty and the bars are iron bars. We used to have break ins. It looks like prison window now.

Will this window get a lot of strong sunlight exposure? If yes, then I would choose a "traditional" ,solid, light color lining instead of having the printed fabric as the lining.

On my bedroom drapery, I like to use "blackout lining" that makes the room darker (when drapes are closed). Also, it keeps the room cooler in hot weather, warmer in cold weather.

Are you planning on opening and closing your curtains?

The window is a southern exposure, so lots of light. I don't know how to add a lining. There will be not two curtains. Just one big piece as its really wide and cutting it down the middle I am bound to make a measuring mistaking that way. Its 54 inch wide decorator fabric. If making two curtains that open and close it would too wide to fit them both. I have to post a photo when I am done.

What is the width of your window?
Have you already put the drapery rod up?

Very nice! The colors on the fabric are cheerful. The palms & flowers go well with your name - tropical_thought : )
I bet it makes you happy to walk into that room!

I reposted the photo because it was sideways. I have to rewash/reiron it, but I got it up. You can see the light shining through. Yes, my screen name is about tropical things like Palm trees. Thank you.