There are very few public toilets in Colombia. In their absence use a restaurant's toilet. Museums and large shopping malls usually have public toilets, as do bus and airport terminals and some supermarkets.
You'll often (but not always) find toilet paper in toilets, so it's wise to carry some with you. Never flush toilet paper. The pipes are narrow and the water pressure is weak, so toilets can't cope with paper. A wastebasket is normally provided.
The most common word for toilet is baño. Men's toilets will usually bear a label saying señores,hombres or caballeros, while the women's toilets will be marked señoras,mujeres or damas.
Bus-station restrooms will usually charge COP$800 to COP$1000 plus COP$200–300 for toilet paper.