Im guessing these are chicken eggs? When you get your bator you will want to set it up and let it run at least 12 hours to stabilize, 48 hours is better. Set up in an area free of drafts. Perferable in climate controlled room with temps in the range of 70-75°F. Away from windows, sun light or other heat/cold sources. Temp of the bator should be set at 99.5°F, you will want your humidity to be in the range of 40-45%
You will need an independant accurate, reliable thermometer and hygrometer. The ones that come with the bator (if digital thermostat and hygrometer) are not very accurate nor reliable.
With shipped eggs you will want to let them set for 12 to 24 hrs at room temp with the pointed end down. This allows the egg to settle from the rough handling during shipping. If the outdoor temp is above 70°F during shipping, I place the eggs in the bator when they arrive with the turner off for the settling period. This being that the eggs will have started to incubate, thus letting them set at room temp for the required time will end up killing the embryo. If turning by hand you can do the same thing just not turn the eggs while settling. Also, if turning by hand you will want to mark the eggs with an X and O on opposite sides or numbers 1 - 4 , equal distance apart on the eggs. This allows you to see that the eggs have been turned. If using automatic turner, this is not necessary.
Incubation period for chickens is 21days. After 8 or 10 days, you can candle the eggs to see if they are fertile. You should be able to see "spider veins" if they are fertile. You can candle them again at 10 or 14 days and tell if they are still developing or have (dis) "died in shell". Some people candle again before putting them in "lock down", this is 3 days before the hatch date, usually day 18. You should be able to see movement of the embryo at this time, it will also be dark with a light area at the top of the egg, that's the air cell. By doing this you will know for sure the egg is viable and should hatch or it's a "dud" and won't, a "clear egg" is an infertile egg.
Some may hatch early, some late. The majority should hatch at approximately around the same time.
There are many good sites on the web for incubating eggs. The best site is here, BYC! Look at the Incubation and Hatching threads here and ask lots of questions. Wish you the best for your 1st time. Hope this has helped you to understand a little better the how, why involved in incubating eggs. If I can be of further assistance, don't hesitate to ask!
