When my daughter was younger, she wanted daisies in her room. I found a daisy comforter at Walmart, and bought an extra set of sheets to make her curtains.
I printed out some daisy clip art in large sizes and put them in frames. She wanted white frames, but I only had brown wood. So I just spray painted the frames.
I also printed out lots and lots of little daisies and glued them all together to make a poster-sized collage.
We painted her furniture and sponge-painted daisies on it as accents.