The main focus of LSAT preparation should be to take lots of practice tests.
The reason is simple: The LSAT that you take is going to look like the practice tests.
(not like a book of only one specific problem type)
Thus, taking a practice test is the closest way to simulate taking the actual LSAT.
Another benefit of taking many practice tests is you will start picking up on the patterns of the LSAT (possibly without even realizing it). This is very helpful because every question on the LSAT fits into one of only a few possible patterns.
However, using a variety of ways to prepare for the LSAT is also important because it will help solidify concepts by making you apply them in different ways while having the added benefit of making LSAT preparation less boring by mixing things up.
Here’s some examples of ways you can mix up LSAT prep:
Listen to explanations by people who are better at the LSAT than you and explain to people who are worse than you at the LSAT (or do not know the LSAT at all) — talking through problems will help you understand concepts.
Re-do questions you got incorrect on a practice test and re-do questions you got correct on another practice test.
The idea is to make the reasoning you use on the LSAT become second nature.