Oh...oh...oh.... I LOVE my design wall...made it out of the super light weight foam insulation sheets, I got two sheets from Home Depot, even talked the guys into cutting it for me, right down the middle. I purchased 1" and 1-1/2", like the 1-1/2" the best.
I used Super 77 Multipurpose Adhesive by 3M. I had white all cotton flannel that I cut to fit and covered top to bottom. Then I used Gorilla Tape (much stronger than Duct tape)on the back to hold my two 2 foot pieces together, and now I can fold them in half and store behind my door when needed......
My "Sewing Studio" is upstairs, so I put my design wall first infront of my closet in my room, but as my project starts to grow.....I move it out to the hallway, that way I can look at it from a farther distance, which is really needed some times. With the flannel it will usually 'hold' a simple block, but as my pieces start to be sewn together then I use pins....when not in use I store then pins on the side of the foam sheets......Oh how I love my wall.........