How to prepare for a colonoscopy?

Good morning, on Monday, June 10, I have a colonoscopy at 12:00. On the card I received, it says that I drink the first portion (two sachets) on Sunday (the day before) from 6:00 p.m. every 15 minutes, i.e. until about 8:00 p.m. On the day of the colonoscopy, he writes that 4 hours before the examination, the next two hours, i.e. from 8:00 to 10:00? In addition, it is also written that fluids (on the day of the colonoscopy) are drunk up to 4 hours before the test, so it turns out that until 8:00 a.m. Is it well written? Do I understand it correctly? Please help. We are talking about Fortrans