Pretty much what they said. Different people use different techniques but good shed construction is good. I don’t use screws and fender washers to put my hardware cloth on. I rip strips about ¾” thick from a 2x4, drill pilot holes to assure the wood doesn’t split (plus it’s easier to start the screws), and screw those over the ends of the hardware cloth, always going through a hole in the hardware cloth. If you tighten it down that’s really secure plus you don’t snag clothing or skin on the ends of the hardware cloth. But screws and washers work too. There is no one way that is right where every other way is wrong.
What mistakes have I made, eh, eh, I mean do I have any suggestions. Don’t use insufficient hardware. Hinges need to be robust enough to carry the load as well as strong enough that a raccoon or big dog can’t rip them apart. Same thing for hasps or however you lock it. Make sure your closure will fit in the hasp without being too tight. Don’t use sliding bolts or something that simple as a closure. Use something you can lock. I use S-biners I got from Lowe’s to secure my hasps. So far it has worked.
Realize that many things climb and can squeeze through a very small hole. I arbitrarily chose 1” as my guide. Any opening larger than 1” gets covered in hardware cloth. Doesn’t matter where it is.
Gates and doors can be weak points. Make sure they fit reasonably well and are secure.
External nests that penetrate the coop wall can be a weak point. If you build them strong they are fine but sometimes it’s a way for rain or predators to get in. Firmly attach them and use hardware and materials sufficient for the job.
I personally like a coop that I can walk into. I go inside to collect eggs, lock the pop door at night, and such. That way the coop gets a security search before I lock them up. I’ve walked in on several snakes and even a possum once. I once had a skunk in the run but the chickens were already locked up. I secured that breach the next day.
That’s enough. Use decent technique and materials and you should be OK.