Hi @Medora -
A key part of practice is taking realistic full-length exams under test-like conditions. As @fitdoc010996 pointed out, AAMC materials are the gold standard since they're the official test-makers. Doing practice passages is key, but you also want to make sure you get some experience simulating what it's like to a do a FL exam. For instance, when it comes to practicing Bio/Biochem passages, it can feel very different to sit down and do practice passages in isolation in comparison to working through 10 passages + some freestanding questions after you've already spent hours racking your brains on the Chemical/Physical Foundations and CARS. Depending on what your personal sleep cycle is like, you may also want to practice what it takes to get to 100% focus at 8 am! Many students find that they want practice with this beyond what the 3 AAMC FLs (+ unscored sample), especially if they want to save the AAMC materials until the end.
Best of luck getting started 🙂!