Okay if you have chicken poultry, you will move down on day 18, count 24 hours from putting in as first day. take off turner, if you have one, lay on their side, no more turning, Add warm water to trays, make sure humdity is sufficient to hatch your eggs.... depends on you - I keep our chicken ones between 50 and 55 percent humidity.
Once humidity is where it needs to be, leave the incubator alone. Opening and shutting it looses that valuable humidity and temperature is critical to a successful heat. Also it is always a good idea to calibrate your hygrometer and thermometer before a hatch!
Praying you will have a successful and happy hatching!!!