Anything special i need to know when changing my anti-freeze. this is my first time, trying to save money. someone said something about getting the air out? what does that mean?

Drain the coolant, connect or close all hoses and drain plugs,start motor and fill radiator with a 50/50 mix of water and anti-freeze, leave engine running,when motor gets hot the thermostat will open allowing the coolant to flow through the motor, in change the anti-freeze will get lower in the radiator thus you continue to fill untill full and the radiator will not except more coolant, ( this is how you get the air out) replace radiator cap and fill reservoir to cold level and your done. Recheck your coolant reservoir after you have driven the vehicle a bit and fill if necessary, do not fill to top, only fill to cool mark. the reservoir is not under pressure so you can fill at any time motor hot or cold

Drain the system as best you can from the petcock on the bottom of the radiator, refill while idling with pure water, allow it to reach operating temperature, drain the system again. Refill the system, leave the cap off and add as needed. It's hard to drain the system fully just from the drain on the radiator but using the same type of coolant is a must. If it's red get the dexcool coolant, if it's green stick with a good brand. The system will burp itself over the course of filling it. Once it's back to operating temperature make sure it's blowing heat from the vents and you're good to go.