Well, I am the one who made Lala's...let me see if I can describe how I made it-I made about 10 of them all at once.
I cut a peice of card board in two peices-The size you want the board to be when it's opened. I cut 2 peices of felt about 2-3 inches larger than the cardboard. I sewed a pocket with the felt, and then sewed in a 'binding' so it would fold, slipped the cardboard in, and sewed shut.
Pretty easy. Cutting the cardboard it the hardest part.
I did cut the felt shapes free hand-it was an under water theme. (I make super cute crabs and seahorses-imo!) You could use kids' stencles for a pattern, and I just bought sponges that are cut in shapes that are supposed to be used for spong painting, but I thought that they would be great felt board shapes-but anything is fun really, My dds like regular old shapes as much as anything else.