A while back I received a roll of mounting adhesive. I FINALLY started using it and am loving it. The product is 3M's Positionable Mounting Adhesive. It works like a dream for delicate or thin papers. The adhesive comes in a roll that you unravel. The item you want to adhere is placed (side up!) on the roll and cut out. You then rub the back side of the item on a special paper with a special utensil (all included with the roll.) Now you take off the backing and attach it. If you don't like the position pick it up and try again. It is repositionable until you rub down the front side.
The cover looks much smoother than ones I created using PVA. There is no time wasted waiting for glue to dry. This is a great product!