Bake a perfect cake every time by Rena Cook | May 27, 2013 | Cooking Tips, Tips Keep in mind these few tips and your cakes will always come out perfect. Don’t forget to sieve the flour. You must always preheat the oven. Don’t open the oven door at all, at least for the first half hour. After you take the cake out of the oven, let it cool down for 5 minutes before tipping it over on a cooling rack.