Sometimes dragons will dig around or scratch around for weird reasons so it isn't always that the dragon is going to lay a clutch, that just happens to be the most common. My female likes to dig, but is under a year, so too young to be laying, though I believe yours is the right age.
Don't be afraid of sounding ignorant by asking questions, this forum is here to help people and the community is actually quite friendly.
Making a lay box isn't that difficult - it just varies from person to person. The rough rule is that you get a container that is big enough to contain at least 9 inches of substrate and ample digging room for your girl. Some people use containers that are sized to fit inside the enclosure while others have almost an isolation tank for the sole purpose of a lay box. This works in the sense that once the digging behavior starts, they will remove the female from her enclosure and place her into the lay box for some personal time. The time left varies.
I'd recommend for substrate you use something like a mixture of Eco Earth + Play Sand. You want the mixture to be moist enough that it is sand castle consistency. Enough that she can bury and dig, but not cave in on her.
One thing is for certain, you'll want to do this ASAP and determine whether she really is gravid. If she doesn't have the proper conditions to lay, and she is carrying eggs, there's a chance of her becoming egg bound.