My sewing room also doubles as our guest room and we recently replaced our sofabed with a new Ikea day bed that I had been coveting for a number of years. I wanted something nice and bright to cover it so I designed myself a quilt. I went old school and drew it out on a piece of graph paper.
I brought a queen sized sheet to use for the backing (if you can get them on sale, they are very economical to use as quilt backs) so I used the measurements of that to work out how big the squares needed to be plus seam allowance and got to cutting out.
Then I was ready to sew
I sewed all of the squares into strips then all of the strips together to make the top. I used a polar fleece blanket for the batting as they are much cheaper than buying quilt batting and are lightweight and warm. I sandwiched all of the layers together, wrangled it through my sewing machine (in 2 bites) and added the binding. I really enjoy the last step of hand sewing the binding to finish it off. I am so pleased with how it turned out and it looks better than I thought it would. It looks great on the bed and I had enough fabric left over to make a couple of cushion covers as well