Which law schools are you interested in applying to?
Have you only taken the LSAT once and only have 158 on your LSAC record?
When are you planning to apply and subsequently start law school?
How much time did you spend preparing before taking the December test and how did you prepare?
Since most, but not all, law schools now focus on the highest reported LSAT score rather than average score when evaluating applications from people with multiple reported scores, if you can score significantly higher than 158 on a future administration you should re-take the test. Of course the decision depends in large part on the admission numbers ranges of the schools you are aiming for since your current numbers qualify you for admission to many lower ranked schools, so knowing the admission statistics of your target schools is critical to your question.
I was hoping for University of Texas, Georgetown, or UVA. But those according to the LSAC counter is out of reach.
I have only taken the LSAT once, and I got a 158.
I am planning to apply this summer, and I want to apply this summer as well (before Sept.)
I would like to start law school this fall.
I took Testmasters class last summer to prepare me for the October test date. I didn't feel prepared so waited for December test date. I used the time in between October and December to continue studying. Taking two practice tests a week, and studying question types and logic games. Between October and December, the only thing I did was study. I didn't have a job at the time.
Since I have been toying around with taking the exam, I have taken another practice test and I scored a 164. I have been told though that the day of the actual exam, most test-takers score at least 5 points lower than they did on practice tests.