Step 1: Collect all the stuff you'll need
The pattern won't tell you this, but get some sheet foam, like an automotive headliner from the fabric store and use it as interfacing. It helps the dance pad vinyl look less wrinkly.
You'll need sharp scissors and a sewing machine. Depending on the style you choose you might need some zippers or similar fastener hardware.
Step 2: Cut up the Dance Pad
Step 3: Smooth out the wrinkles
Step 4: Cut out the front and back panels of your purse
Step 7: Sew the foam to the Dance Pad and sew the lining and pockets
Here I'm just sewing the foam and the lining and the dance pad all together.