I think one thing all chicken keepers recommend is getting a coop bigger than you think. It is often called "chicken math," or more specifically, "chicken addition". When I started, I did not know this and ended up just making more coops. Now I have three small coops to clean verses one big coop.
Another tip is study the breeds you plan on getting. If you want layers and pets I recommend Barred Plymouth Rocks, along with Rhode Island Reds. If your area is cold, you could try Buff Orpingtons (they lay very well in the winter and are one of the best family breeds), but the downside with this breed is they eat a lot.
If you are getting chicks then get more than you think you need both because they are addicting and you are likely to lose some.Go
One life-saving tip is to explore the articles on BYC.
Glad you are getting into chickens! If you have any questions feel free to ask! Wishing you the best of luck!