A table, desk, or even a bed can be used to flatten the map or poster. Provide enough space for the item to lay flat when unrolled. Sweep off any debris before you begin. You wouldn’t want to fix a poster of your favorite musician only to see a crumb lodged in their face! Slide the item out of any wrapper or container. Set the roll on one side of the flat surface. Feel for the end of the map or poster on the outside of the roll. Don’t pinch the the outside border or else you’ll crease it. Roll out the item until it is spread out on the table.  Usually you will need to place the item facedown. Posters for example are rolled up so the image is on the inside. You will have to unroll it and place the image side down. If your item ever feels resistant to opening, don’t force it. Instead, try humidifying it. Posters are shipped through the mail in tubes that can also be used for flattening. Toilet paper rolls are smaller but still work very well. Paper towel or wrapping paper rolls also work. Align the tube in the center of one end of your item.  It’s possible to try flattening without using a tube. Simply roll up the map or poster as tight as you can and bind it with rubber bands. It’s best though to use a tube so the item doesn’t get dented. Keep in mind that you need to roll your item in the direction opposite the curl. Flip your map or poster to the correct side before placing the tube. Hold the end of the item tight to the tube as you begin to roll it towards the opposite side. Work slowly and gently. Start loose and tighten the roll as you go to avoid creases. Sometimes this will be enough to flatten a map or poster. Rubber bands are a good binder since they’re not likely to cause damage to your map or poster. Place one around each end of the roll. Tape can work, such as the tape often used to roll a new poster, but some tapes can lead to ugly rips. If you’re worried about the rubber bands or tape damaging your item, lay the map or poster flat and cover it with heavy objects. A new poster will need to stay in...

How would you rephrase that briefly using Indonesian?
Bersihkan area yang datar. Buka gulungan peta atau poster. Letakkan tabung kardus di salah satu ujung poster. Gulung map atau poster ke arah yang berlawanan dengan gulungan awalnya. Ikatkan karet gelang di gulungan tersebut untuk menahannya. Diamkan gulungan ini selama satu jam. Lepas karet gelang dan buka gulungan peta atau poster.