TIR, or Test Information Release, is one of the ACT's most undervalued services.
Three times a year (for takers of the December, April, and June tests), the ACT allows you to pay $32 in exchange for a copy of the actual ACT you took, a copy of your answers, and a copy of the correct answers. This resource can be of IMMENSE value if used properly.
Step one: when you receive your test in the mail, reread over the test, pausing on the questions that you missed. If you recall guessing on a question (which you happened to get right), also pause here. Think: what was I thinking when I took this question? Jot it down on paper for each and every question missed.
Step two: look for patterns in your thought process and patterns in the questions you are missing. In the Reading test, for example, are you consistently missing questions that ask for main ideas? In English, are you repeatedly missing questions of comprehension? In Math, are you repeatedly missing questions of Trigonometry? In Science, are you repeatedly missing questions that test your ability to compare the data of different charts and tables?
Step three: don't give up this test until you've learned to get every question correct (within reason). This is your chance to both refresh yourself on and learn content and skills. Get a good prep book or look to Youtube or another resource to help you fill in the gaps on what you are lacking.
If you are taking the December, April, or June ACT, be sure to take advantage of this opportunity. To learn more, go here: http://www.act.org/content/act/en/products-and-services/the-act/scores/request-a-copy-of-qa.html