The Texas Education Agency website (see Resources) has study guides for the math TAKS test for grades 3 to 11. Guides for Spanish-speaking students are available for grades 3 to 6. These guides present skills reviews and practice problems for each grade level. The problems focus on what you are expected to know for the TAKS test, such as geometry and measurement for sixth-grade students. Spend time working through the guide for your grade, paying special attention to areas you find difficult.
The Texas Education Agency website (see Resources) also has old test questions with answers. You can print out these problems or use the interactive tests online. The printout is recommended, because you may need to use a ruler and the online version isn't to scale. Work through all the problems appropriate for your grade level and then look up the answers. The problems you missed are areas you need to work on.
Once you have completed the study guides and released tests from the Texas Education Agency, you will know the areas in which you need more practice. Find a math study guide at your library or purchase one that focuses on your trouble areas. Spend at least 15 minutes a day learning the principles and working on problems to get better at them.
Using one of the released tests from the Texas Education Agency or a practice test from another online source, set up a test-taking scenario. Sit at a desk with the tools you are allowed to use for your grade level (such as calculator and ruler) and set a timer for the time allotted for the math portion of the TAKS test. Practice working calmly and thoroughly through the problems.
The day before the test, do not cram. Study as normal, set out the items you need for the test, then put your books away and get a good night's rest. Eat a breakfast that is satisfying but not too filling. When you receive your test, scan it quickly. Work on the problems you find easy. This gives you the rest of the test time to work on the harder problems. If you get stuck on a question, move on and come back to it at the end. If you have extra time at the end, go over your answers.