When your shirt comes out of dryer, shake it out, smooth it with your hands and hang it on a shirt hanger. Button the top button. Fill the iron with filtered tap water, or tap water mixed with distilled water at a 50/50 ratio. Tap water contains small amounts of minerals which build up in your iron over time. This leads to clogging. If you notice that your iron occasionally spits too much water out, it is because it is clogged.   Distilled water, on the other hand, can cause your iron to corrode more quickly due to the way water molecules combine with carbon dioxide in the surrounding environment.  Check your manufacturer's suggestion. Some irons are safe to use with unfiltered tap water, while others are safe to use with distilled water. When in doubt, a 50/50 blend or filtered tap water would be your safest bets. A shirt that is wrinkle-free takes a cooler setting than the hot setting for cotton. Be careful not to burn the shirt.  See manufacturer's settings. If you are ironing more than one item, you will want to either fold those items as you complete them or hang them. This will prevent them from wrinkling again while you finish the other items. Lightly spray the hanging shirt with sizing or spray starch (optional) then remove the shirt from hanger. Unbutton the top button.

TL;DR in Indonesian:
Mulailah dengan kemeja yang baru dicuci. Isi seterika Anda. Biarkan seterika Anda mencapai suhu yang tepat. Siapkan tempat untuk menggantung pakaian. Semprotkan sedikit kanji.