There are really only two things you need to know to make perfect candy popcorn:
1. Cook it to the right temperature. If you want it ooey, gooey, cook it to 260 degrees. If you want a hard coating, cook it to 300 degrees. Use a thermometer.
2. Use plenty of candy syrup. You want enough candy to coat every kernel. A recipe that calls for two cups of sugar for 1/2 cup popcorn kernels is about right.