10
This is such an important step. Before you even start grabbing things or getting stuff from the cupboard, read the recipe and make sure you have the ingredients the recipe calls for.
Read the reviews, lots of times people have great baking tips or other great options if they find something didn't work.
What's that old saying? Measure twice, cut once! The same thing goes for baking. Baking is a science, and for the best results, accuracy is key.
Unless otherwise instructed always preheat your oven and make sure it is at the proper temperature before using it.