Puzzles must be folded of course. We place them so that we can see the image.
Put wrapping or office paper under the puzzle. Check that paper is under all puzzle.
On the top of puzzle (yes on side where is the image) we pour the required amount of adhesive (one glue is for about 2,000 pieces puzzle). Spread glue evenly throughout the puzzle. You can use harder cardboard, brush, etc.
Your entire image turns white from glue, but do not worry !! Let it 1-2 hours :))
Thus glued puzzle you can hang on the wall or frame or put in glass.