The Do's, everyone will tell you them, here are the don'ts that I have learn't the hard way, i.e personal experience
1) Don't bake till you have at least once seen someone bake either in real life or on TV or an authentic video. Small Things like how to fill, grease, flour and line the pans are very important.
2) Before you start out, have all your things together. The cookware, the spoons, whips, ingredients, measures....everything in place. My routine cooking is very intuitive. I start cooking, then walk around the kitchen, gather stuff and ingredients while I am cooking and that works fine for me for my roz ka khaana. NP claims I am a great cook, which I believe he says to convince himself and to gear himself to a lifetime of my radioactive cooking. (OK, I am not that bad, but not great either, a little better than average is quite where I am). But baking requires a little more effort than your routine cooking. At least in the beginning. So be well prepared.
3) Read the recipe carefully. Trust those from good books. Sites I am not sure. Cooking blogs are generally good, but do not go by the pics. Awful stuff can look awesome in a few fancy photographs. If a recipe seems complicated, please stay away. Use your intuition before you cook. This is presuming you are a newbie like me (since you have reached so far). Start with simple things first. Like a basic sponge cake.
4) Follow the sequence, yes. But do not take things THAT seriously. Like at the fag end of the recipe they will tell you to drop the mixture in greased and flour dusted tin and put it in an oven preheated for x minutes. No one will tell you that the tin must be greased and dusted before you begin. And by the time you are done the oven better be pre heated. Once the batter is made, it must be baked soon. Leaving it out for long will result in cakes that do not rise enough.
5) The tooth pic/knife/fork test, again do not take it SO seriously, the way I did. Kept poking my cake so often that it looked like a pock marked cake by the time it was fully done! BTW also beware, opening the oven too often during the innumerable fork tests is not good, the heat is lost out.
6) Prepare small portions at the oust. Expect some wastage and failed experiments before working out exactly how much heating your portions, your oven need. My first cake had a charred crust and rest was fine after I literally tore off the crust. Second was absolutely tasteless and charred mess. Third was too dense and sweet but overall not bad. Fourth attempt a year later with previous gyaan was much better but past "burns" made me poke it too often and my cake collapsed and got dense as the poking spoiled the top and let the air inside the baking cake escape.
7) Remember, Fahrenheit and Celsius were two different people with contributions to science similar yet different. So read carefully the temperature stated on the recipe and carry out appropriate conversions. Your oven may still need different temperatures so watch your cake get baked, this is not the time to watch that silly reality show on TV.
8) Finally, whatever you do, whether the outcome is a good cake or a damaged cake, your kitchen will end up smelling like heaven (that is how I imagine it smells), of course unless you char it way too far. And do not get discouraged, its really not rocket science, baking cakes, only practice makes one perfect. So happy trying.