Definitely get the official SSAT online practise, it’s a godsend. It helped me more than ANY other resource, though perhaps that’s just me. It comes with lessons, mini practises of 5-10 questions, and practise tests in each section as well as mock tests (all sections).
Verbal: Quizlet, and find lists for SSAT words online. This is the section you want to start practising first, to make sure you have the largest possible archive of words in your head when you take the test.
Reading: Read more books, practise. Keep in mind practise test scores may not reflect the actual test scores very well in this section, as it seems like genres and types change quite a bit.
Maths: Practise competition maths questions that are very similar to the SSAT itself. There’s a reason that competition maths kids seem to find the maths section a breeze. Tests such as the AMC 8/10 (12 is harder than SSAT) and the UKMT JMC/IMC/SMC are formatted almost identically to the SSAT maths section, and would be very worth checking out.