When you turn on the heat in
your home, make sure you humidify your guitar if your house humidity
drops below 40%. There are many types of room humidifiers and
furnace add-ons available to put moisture back into the air. I believe
this is the best way to protect your guitar.
If you prefer a guitar case humidifier instead, try keeping your guitar in its case when you aren't playing and put a humidity gauge "hygrometer" by the heel of the neck of the guitar to monitor things. There are several small guitar humidifiers available and they all seem to work about the same. They consist of a sponge or a porous stone that you soak with water and leave in the case usually in the accessory compartment. You have to remember to soak it periodically. Follow the instructions that come with it from the manufacturer. Don't over-do it. Just remember to moisten the sponge regularly as needed, don't put it where it might do water damage to the wood or finish of the guitar, and monitor the humidity in the case using the hygrometer. The humidity should ideally be around 45%. Remember, high humidity can also harm your guitar as well. If the humidity gets too high, use a silica gel pack inside the case to absorb the moisture.
Bob, Gman ( o )==#