This one was really a challenge for me! I've decided that I really have no idea as to how to go about a one layered card. It took weeks of thinking about how I was going to approach it and I'm still not really happy with the end result.
I am entering my card into these challenges:
Flat Friends - One Layer Card
The Outlawz Saturday Challenge - Get Well
I have used a single layer of cardstock with the image from Flat Friends printed on to it. I coloured with copic markers. I added a Get Well Soon sentiment with a Zig Marker and some lines with a Distress Marker. I used a different Distress Marker to add some parallel stitching lines across the corner.