It's time for fairs around the country and Montana is no exception. I spent some time at the Western Montana Fair held in Missoula and made pictures both during the day and at night. You can see that the time of day makes a big difference in what the carnival looks like!
If you're photographing people during the day, be sure to turn on your flash. It brightens the shadows on a sunny day and lightens your subject if the sky is gray. At night, do the opposite. Put your camera on a tripod and turn off the flash to record the lights of booths and rides. If you can, shoot from a high vantage point for a different perspective. I was on stairs leading up to (of all things) the Photography display.
Try visiting the fair more than once. The light and weather may change and you'll become more familiar with the best angles and subjects for pictures during the day or night.