These lined pouches are made unusually following a crafts channel (Corinne Brad) tutorial. I used a pony tail band rather than the fabric loop suggested so I could stretch them around dog leashes and never forget pooh bags again.
To make sew the two short ends of lining and outer fabric rectangles together (wrong sides facing) then press over the flap to mark a crease. Sew from crease to top end on each side then manipulate fabric to fit the other seam into the crease and sew the remaining sides (leaving a turning gap in one lining side and tucking in the loop or band in one of the outer sides). This makes a weird three flapped object but when turned and pressed it is a tidy, quick clutch.
To finish I top stitched in places and put in a snap. At last, I am using my bargain bag of pony tail bands.