When you first open the box, you must go through all the pieces and take out any that have a red marking on it. These are scraps from the manufacturing process, which probably aren't thrown out due to how the item is manufactured. It will take a few minutes to sort these pieces out, and you can sort the actual pieces while you do this. I suggest by color to help making the building process easier. You should also keep the scraps, just in case an actual piece makes its way in the container you put the scraps (which happened to me). The pieces are thicker than jigsaw puzzle pieces, and are pieces of foam with a thin piece of cardstock on the front. They are very durable for testing out the wrong combinations, even after ten to twenty attempts on a single piece. Putting the puzzle together may seem intimidating at first. It's best to do each individual building. It was difficult to figure out how the Weasley building looked, since the pictures on the box are rather vague and you have so many similar-looking pieces. If you're doing this with more than just yourself, you should probably take a picture of the box with your phone since everyone will need to be looking at it quite often. It's easy to get the pieces for the back and front of the building mixed up, but there is no problem with fitting. You will be able to clearly tell when a piece will fit, usually by how it doesn't fit together properly. The only exception is the floor, which you will need to look at closely to ensure the pavement looks proper to indicate you have connected the correct pieces. Each side was built individually. So, the front, the back, each section of the Weasley building, the leftmost side, the roof pieces, and the floor. Once you have everything assembled, it's time to make the puzzle 3D. Included are instructions to do so, but they don't show what the pieces look like, just generic-looking jigsaw pieces. You attach the walls to the floor, and then the roof with the chimneys. Putting the puzzle together for the 3D part was the most frustrating part, and it doesn't look 100% stable. They give you pieces (which you will have no idea what they are for until it's time for the 3D part) for keeping the Weasley building together, and one for the middle of the buildings. The roofs have an issue of looking a little caved in. We made all the chimneys face the front since we liked the way it looked better than what was on the box. With two people putting this together, it took about four hours. The process was slow at first, but it got easier once we got used to how the puzzle was being put together. Although it was frustrating at first, it was a very fun project, and I would recommend it for a jigsaw puzzle enthusiast, even if they don't care for Harry Potter much.