First, double-check all of your plug connections. Make sure you have a tight seal.
Second, make sure any light strands, extension cords, or other connections you are using are rated for OUTDOOR use. Power cords that are rated for indoor use are not waterproof. Any moisture will cause an indoor power cord or indoor light strands to trip a GFCI.
Third, make sure you are not plugging too many things into the same circuit going above the amperage rating. If you are tripping a breaker and not just the GFCI, you may have too much current being drawn on a single circuit. If you are having problems with your breakers tripping, we recommend that you try using a different outlet that is not on the same “problem” breaker circuit. If you have re-routed your power cords to a different circuit and you are still tripping breakers, we highly recommend you contact a licensed electrician to help you figure out what and where the problem is.
Here’s an article about GFCI trips that may assist to further understand GFCI products.