This will assist you in grasping the test's pattern, content, and other relevant aspects and criteria. Most significantly, it will highlight your strong points as well as places where you need to improve.
Starting early allows you to properly prioritise your tasks while also giving you plenty of time.
Taking a number of practise tests and analysing the results after each one could be enough to get you your desired score.
If you have the time, it's also a good idea to prepare in two stages.
Stage 1 (3-6 months): In this stage, you will strengthen your SAT fundamentals. This could take anywhere from 3 to 6 months, depending on your current situation. This step is optional for those who scored 1350 or higher in the mock.
Stage 2 (1-2 month):This is the stage where you take a lot of practise tests to improve your test-taking and time-management skills.