Practise more when the method is sound and the remaining problem is fluency; change the method when repetition keeps reproducing the same failure. More practice helps when you understand what to do, can recognise and correct mistakes, and performance is improving with repetition.
A method change is more sensible when hours increase but the same errors remain, when revision creates familiarity without recall, or when practice never reaches the form required by the examination. Before changing everything, identify exactly what the present method is failing to produce: understanding, memory, transfer, speed, accuracy, or exam execution.
Use the Study & Learning Methods Hub to compare better learning methods, and the Diagnostics & Recovery Hub if the real weakness is still unclear.