In order to hatch fertile chicken, duck, turkey or other domestic poultry eggs, you need a broody mother bird, or an incubator. If you have the money for it, you can buy extremely functional styrofoam incubators for just over $100 (and smaller, 3-4 egg "classroom" dome models for less yet). And of course you can always pay a lot, lot more. But if you don't want to spend that kind of money, it is still possible to put together a functional "forced air" box incubator at home for just a few dollars, using items you may have around the house or can buy readily at any grocery, thrift, or drugstore (except for the thermostat, which you'll find at Home Depot or other hardware store.)
My total cost for the incubator in this Instructable was about $30. Your cost may be less if you can salvage or re-purpose parts you already have around the house.
Estimated assembly time once you have all the bits together: about 2 hours
You will need:
Serrated knife or hacksaw blade
Sharpie pen or other marker (to mark on the wire and cooler, not the eggs)
Pencil (to mark the eggs if desired)
1 styrofoam ice chest, the thicker-walled the better (I got my Omaha Steak shipping box free by asking on Craigslist.)
1 bottle lamp assembly (Home Depot, about $10 - I salvaged mine from a lamp from a thrift store for $6)
1 lower-element, single pole water heater thermostat ($7.57 at Home Depot)
1 25 W bulb
1 12 Volt transformer (from any defunct electronic device)
1 PC Core fan (scavenged or a dollar or two - I got mine from PC Recycle for $2)
1 plastic (preferred) or glass from an inexpensive picture frame ( I salvaged mine for $1 at a thrift)
1 shallow dish for humidity
Wire hardware cloth (about $9/roll if you don't have leftovers from another project)
1 indoor/outdoor probe type thermometer/hygrometer, about $12 at Home Depot or Walmart
1/2 C salt
1/4 C water
Large zip-close plastic bag
For candling: 1 Mag-Lite flashlight or other similar extremely bright light
A source of freshly laid, fertilized eggs (NEVER refrigerated)
To increase humidity rapidly: a spray bottle of water
Step 1: Put window into top of cooler
Remove the plastic or glass from a picture frame. I think plastic is safer, less prone to breakage. Place it on top of the cooler and trace around it. Remove the 'window' and set aside..
With your serrated knife or hacksaw blade, cut inside the marked line at least 1/2", so that the window overlaid on it has a solid area of support, all the way around.
Tape in place with duct tape. I use yellow because it's what I had in my garage.