First of all, welcome to the forum!
Changing your coolant is pretty easy. Put the bike on the side stand. The coolant system is designed to use the angle of the side stand to keep the air bubbles out.
Pop the radiator cap, and remove the drain bolt, which is the lowest bolt on the water pump itself. When that's drained out, just flush it a bit with the garden hose.
Replace the drain bolt.
Remove the cover from the overflow bottle and use a turkey baster with a hose taped to it to remove the old coolant from that bottle. Remember that coolant is usually toxic, so best not to use your wife's cooking baster.
You have to silicate/phosphate-free coolant. You can use the Honda pre-mixed stuff, but the Prestone "Mix with any color" Extended Life coolant will fit the bill (and your wallet) just as well. If you have to mix your coolant of choice with water, be sure to use only distilled water. Regular tap water can cause you trouble down the road.
It should hold about 2 quarts of coolant. Fill it right to the top of the filler neck, and leave the cap off. Now start the engine and blip the throttle a few times and shut it off. You don't want the engine to heat up, but you do want the flow of fluid to knock any air bubbles free. Top the radiator off again if it settled a bit while running the engine. Replace the radiator cap.
Now fill the overflow bottle to between the Min and Max lines, replace the cap, and you're done!
Be sure to dispose of your old coolant in a proper manner, since it's is toxic and animals like to eat it because it testes sweet.
Hope this helps!
Currently Running Stable:
2010 Honda NT700V
1986 Shadow 700
1986 Honda Trail 110 (Postie Bike)
1987 Honda Rebel 450
1973 Honda Mini Trail 50