This is very important as it will allow the water from collecting in the bottom and growing stagnant. If your bottle has a segmented bottom (ie: most 2-liter soda bottles), you will need to poke a hole in each segment. The bottom of most bottles is typically made from thicker plastic. You will need to use a drill or a hot nail to do this. The hole needs to be deep enough to insert the bottle about two-thirds of the way, or where the straight walls start to curve into a dome. If you places the holes on one side of the bottle, rotate the bottle until the holes face the plant. Gently pat the soil around the bottle.

TL;DR in Indonesian:
Buatlah lubang di dasar botol. Galilah lubang di tanah dekat tanaman. Tancapkan botol ke tanah.