Don’t Forget to Rotate
Pretty much every oven will bake things just a bit unevenly. That being said, if you are not rotating your baked items, then you’re making a rookie mistake. Depending on what you’re baking, rotating may be essential for allowing the dish to cook properly and acheiving the best end result.
If what you are cooking is not overly sensitive to heat changes, make a point of rotating the pan or tray every few minutes. I know we said that you should avoid opening your oven door earlier, but if you’re cooking, rather than baking, in most cases rotating is going to be essential for an even bake.