Build a useful personal baseline
Create a repeatable routine that makes your own saved results easier to compare.
Repeat before interpreting
Begin with several ordinary runs instead of using the first attempt as a final reference.
Practice effects are normal, especially while learning a test's controls.
Keep the setup familiar
Use the same device, browser, input method, and a similar level of distraction whenever practical.
Record enough attempts to distinguish a pattern from one exceptional result.
Compare like with like
Compare each test with its own saved history. A reaction result and a memory level describe different tasks and should remain separate.