Anyone with a few maple trees on their property can make homemade maple syrup. Tapping the trees to extract the sap is just the first step. To make true maple syrup, the sap must be boiled to evaporate the water from the actual syrup. You can construct a homemade evaporator in your own backyard so you can complete the whole process of making the syrup at home, without purchasing expensive equipment.
Set up a fireplace or fire pit in your backyard, away from any heavily wooded areas that could catch fire. A simple circle of stones or cinder blocks will suffice, so long as it it large enough to hold your large boiling pot.
Light a fire in your fire pit using dry wood. The wood must be dry, or else it will not heat effectively to evaporate the water. Use newspaper with matches or lighters if necessary to start the fire.
Coat the rim of your boiling pot with a thin layer of butter or margarine; this will help to prevent the sap from boiling over the sides and causing you to lose some of your syrup.
Pour the sap directly into your boiling pot. Do not fill all the way to the top, as you need some room for the sap to boil. Keep adding sap as water evaporates; do not let the level of sap drop below 1 inch, or you risk burning the mixture.
Monitor the sap's temperature with a candy thermometer. According to the Massachusetts Maple Producers Association, the sap will be ready for the next step in the process when the water has boiled away and the temperature is set 7 degrees Fahrenheit higher than the boiling point of water for your elevation.