I have a king size flannel flat sheet on the wall. I use push pins to keep it up and it has worked wonderful for years.Very functional...lots of room...cheap ~which is good.
I have read alot about the foam insulation boards but I can't see where it would work any differently other than it would be prettier. ~(Is prettier a word??) =)

That is all I have as well!

I put a strip of sticky backed Velcro near the ceiling on a paneled wall - too adhesive for a painted wall, then I stitched sew on Velcro to a 7 1/2 long piece of fleece, so I have a space almost ceiling to floor and 5 feet wide that removes easily. The sticky Velcro stays up, but it's not a very public room and I can live with it. The fleece is very grabby. It was a lifesafer laying out thie current quilt as it's mixed colors and I had to do a lot of rearranging of blocks.

I really want a design board. But my sewing room has two walls with big windows, and the 3rd wall is the shelves. So I can't hang one (I love the sunlight). So I use the bedroom just down the hall, and have to put little pieces of masking tape on each piece so they transport in the same order to the sewing machine.

I have sliding closet doors in my sewing room and I covered them with light colored flannel, this works well for my design wall. the fabric will cling to the flannel on its own.

I have two flat single flannel sheets with sides sewn together and a rod pocket sewn at the top. This "design wall" is hung at ceiling height on an 8ft long thin metal rod. The rod rests on two brackets so it can easily be taken down and stowed away when necessary. I also sewed a small rod pocket at the bottom of the sheets for a dowel which keeps themweighted and hanging straight. It works great!

I have tried flannel and its OK but the best design board is made from headliner fabric, purchased in the home dec dept of Hancock's. You don't have to use pins, blocks "stick" and stay. I have a quilt I'm working on slowly and the blocks have been on the headliner attached to my wall for at least two months and not a single block has become loose. I also have a second design board made of the insulation board from Home Depot. You can pin things up on it.

2 screws in the ceiling on which i have 2 loops of chain--i sit curtain rod across from one to the other----pin on flannal back table cloth also from the cheap shop get a canvas [[ready for painting] staple flannel on about 40 cmsx 40 cms place block layout on carry the whole thing over to machine pick up +sew stays in order-----MUST HAVE A DESIGN WALL-----it makeas a world of difference check out you tube

I put a white sheet on top of the bedding on our kingsize bed in the master bedroom. All fabrics show up well on the white background. I like the walk between the bedroom and my sewing room on the other end of our house. If I do that walk enough times each day, I figure I don't have to use the treadmill in the winter. lol We walk at the beach the rest of the year.

I have mine on a basic roller blind and a fabric attached that is gridded and made specifically for a design wall so that fabric sticks to it