There are a number of simple ways you can prepare that will help you achieve a good score. Make sure you have found a firm, straight posture before you begin the test. It is also important to familiarize yourself with the keyboard you are using before the actual typing beings.
Take a look at your environment and ensure that any noises or visual distractions are removed. Throughout the test, make sure you are maintaining proper hand placement over the keys. It is important not to rush during the 1 minute typing test. Do your best to keep your mind focused on both speed and accuracy as you develop a rhythm that works for you.