Turn the lining right side out and place it inside the outer fabric so that the right sides of each piece are facing each other (the wrong side will be facing you).
Match the side seams, and pin one of the open edges together. Sew along the pinned edge all the way around. Iron seams open.
Flip the fabric so both of the right sides are showing. It will be the shape of a tube now and you want the lining on the inside and the outside fabric facing out towards you.
Now make a casing. An inch or so from the top edge of the bag, stitch a line through the two layers (lining and outer fabric), all around the bag. If you want more of a ruffled edge at the top of the bag, start this line of stitching farther from the top edge.
Then stitch another line about a half inch below the first line.
Take out the extra record in the lining, not the one stuck to the fabric.
Heat your oven to about 350F. put a bowl on a cookie sheet, I use a stainless steel bowl or this nifty bowl for making tortilla bowls for taco salad. Then put the record purse on top of the bowl with the fabric draped over the bowl or tucked in between the record and bowl. Just depends on how you want to do it. I have done it both ways and they both work fine.