Sometimes it can be difficult, because you start off with a question (like, why do birds fly away for the winter?), and then you have to figure out how you are going to answer that question (ask them? nope, probably won’t work). It can be tricky, because no-one might have thought of how to do it before!
But it’s amazing to be able to answer a question and find out something that no-one else in the world knows. Sometimes actually doing the experiment can be really really fun as well. I have been able to go out on boats in the sunshine to look for seabirds as part of an experiment; I’ve travelled across the desert in Africa looking for rhinos; and I’ve made tiny lycra suits for chickens! No day is the same 🙂