The best way to start an essay is with a brainstorming session. Consider the topic, whether the topic is you (your personal statement) or an essay on any other topic that was prompted in the application. Write down your thoughts freely, structure is not important, getting all your thoughts down is what matters most. You might even walk away for a while and come back to see if anything else comes to mind. Once you have all your thoughts down on the topic, you can begin to organize them and create an outline from which to construct your essay. Make sure to check your final essay for grammar and spelling errors and ensure that it clearly communicates what you are wanting to express.