Article in English: A sturdy, nicely shaped box would be best.  A good example is a box used for printer paper.  Cereal boxes, tissue boxes, or shoe boxes would work as well.  Also collect four cardboard rolls, these can either be toilet paper or paper towel rolls depending on the size of your castle.  The cardboard rolls will make the turrets on your castle, so make sure that the other boxes you choose are shorter. If you can't find any cardboard rolls, make your own using poster paper. You can make them whatever height you want. Look at photos or illustrations of real castles for inspiration and create a design on paper.  In the case of this article, it's going to be kept simple with just four walls with a traditional rampart design, and four rolls to act as turrets. Then a moat will be added surrounding the castle. If you do design the castle with more complexity, consider:  Creating turrets which are cut out separately and can stand alone. Making one central tall tower for the prince or princess to be stuck in, with a window for the unfortunate royal to stare through. With the box on your working surface, set the four long rolls to each corner of the photocopy paper box (don't physically attach them yet––this gets done later.)  Assess the size of the turrets to the main castle box.  Adjust the turret size if needed.  If you would like the turrets to be taller, you can switch to a longer roll, like a paper towel or wrapping paper roll. To make the turrets shorter, simply cut the current rolls down to size.  Be sure that you measure and cut all four rolls to the same height. Ramparts are the surrounding walls of the castle and commonly have alternating squares and open square spaces.  Use a ruler to measure and trace evenly spaced squares on the top of your box.  Using scissors, cut out every other square to create the rampart walls of the castle.  Another option is cutting a square template from a piece of cardboard and tracing that square all the way around the box. Attempt to measure the square to a size which will fit all...

Summary in Indonesian:
Carilah kotak kardus yang tepat. Tentukan model kastel Anda. Aturlah kardus untuk mendapatkan ide mengenai bentuk kastel. Potong pola benteng pertahanan di bagian atas kardus. Gambarlah pola batu di atas selembar foil aluminium berukuran besar. Tutup seluruh kastel dengan foil aluminium yang telah didekorasi. Tempelkan menara ke sudut-sudut dinding kastel. Buatlah parit di sekeliling kastel. Bangunlah jembatan kastel. Tambahkan dekorasi lain yang menurut Anda dapat melengkapi penampilan kastel secara keseluruhan.