Take practice NBME tests for step one and step two from the Med Friends website (see References). Some sites require money while others are free. Take whichever you are comfortable using.
Write down your practice score test as well as the name of the test. Match the correct test name with the correct score as you must input your score later into the correct window in the score estimator.
Find other practice tests using the Med Friend links and take these tests. Take as many tests as possible. Write all the scores down according to the practice test name and by the step it tests.
Navigate to the "Step 1 Estimator" calculator link (see Resources). Input your score results in the text box for each appropriate test that you took. Don't fill out test scores that you didn't take. Click "submit" to get your estimated score.
Go to the "Step 2 Estimator" link (see Resources) and fill in the score information for each practice test you took. Click "submit" to get your "Step 2" estimated score.