Article in English: You want a rose which has a nice bloom, but also no moisture or flaws.  The moisture will cause molding and the flaws will be exaggerated in the drying process.  You can use blooms which have opened a bit, but don't use a rose which is already beginning to fall apart and lose its petals. Find a room which you don't use often, like a laundry room, attic or a utility closet.  The space should still have good ventilation to allow the moisture to escape.  Stretch a clothes line or rope between 2 points in this room and tie it securely.  Make sure it is sturdy enough to hold your roses. You want to choose a dark space.  The color of your roses will darken in the drying process, but exposing them to light will increase this color change, while using a dark space will reduce the alteration in the rose color.

Summary in Indonesian:
Pilihlah mawar dengan kumpulan bunga yang bagus untuk dikeringkan. Pasang tali jemuran di tempat yang sejuk dan gelap.