I thought I'd write a little tutorial for each step of the bedding process I do, just in case it is of any help. There is a wonderful mattress tutorial by Kris, but for my purposes and time restrictions, I came up with a slightly easier 'cheat' version. But do check hers out - she is amazing!
First picture above is the slat bed I made. The alcove bed is a very strange shape - long and very narrow, but as it is at the back of the room, it looks ok. I had to make a simple bed to fit the dimensions (be nice about my amateur woodworking, I'm practicing!).
Next, I cut out a foam board rectangle that fits snugly in the slat bed frame.
I drew a buttoning pattern on paper using the foam board as a guide.
Then I cut out my fabric to fit. I used cotton that came from a pair of well worn (clean!) pyjamas. You can probably find lots of thins that are suitable around the house. It overlaps the foam board by about 2.5 cm on each side. I used pinking shears to avoid any fabric fraying during the process.
I made a sandwich of the fabric, wadding and buttoning pattern.
Using crochet cotton and a small darning needle, I sewed through the sandwich at each 'button' on the fabric, pulling taut so that the wadding puffs up around the button.
Here's the front.
Then I covered the paper pattern with tacky glue,
Stuck on the foamboard, and glued the edges of the fabric to the underside.
Here's the top.
The mattress fits nicely into the slat bed (the gaps are intentional, for a later headboard).
The slat bed is supported by triangular dowel glued to the walls. The alcove will fit in front, covering up a multitude of sins.
That's the first step... next time, bolsters and pillows!