Find online test practice sites. PsychometricSuccess.com, Shl.com, and Kankakee (Illinois) Community College's website (Kcc.cc.il.us), for example, all offer practice versions of numerical ability tests. Because it is a good idea to get lots of practice, you might want to bookmark them all.
Read the test overview and advice. The practice test sites include information on the content of the test and on how best to prepare for it. They offer tips on which math skills to practice and how to approach math practice. Numerical ability tests typically include basic arithmetic skills, such as addition, subtraction, and multiplication, in addition to fractions, decimals, ratios, percentages and other simple math. You may be asked to interpret data as presented in charts and graphs or analyze a series of numbers. Most of the test practice sites dedicate themselves to helping you perform well on numerical ability tests, so take the time to understand their test prep and test-taking suggestions, and get a good feel for just what is involved in each portion of a numerical ability test.
Find out all you can about the content of your test. If there is any way to get information on what is included in the test you will be taking, take advantage of it. Maybe you have a friend who took the test successfully. Perhaps your vocational school can clue you in to what a certain employer usually tests for. It may be that the test you take will include numerical computation and estimation, but not reasoning or data analysis. The more information you can get about the test you will actually be taking, the better.
Practice performing simple calculations without a calculator. Even if you were calculator-dependent during your school years, numerical ability testing usually restricts the use of calculators. Drill your addition, subtraction, multiplication and division skills relentlessly. Use pencil and paper, and try doing some of the calculations in your head. The more quickly you can correctly answer test questions, the better the potential for a good score.
Take and retake the sample tests under time pressure. You can take the test(s) available at one site and then head over to another to try your hand at a different practice test. Because speed is critical to success in numerical ability testing, it is important to get as much timed experience as possible. This is especially true if you find it difficult to work with numbers. Practice and more practice will allow you to gain confidence and feel capable of performing well under time pressure.