To set meaningful goals, it's crucial to consider the S.M.A.R.T. criteria, which stands for Specific, Measurable, Achievable, Relevant, and Time-bound. Goals should be detailed enough to know exactly what you're aiming for. For instance, instead of saying, 'I want to get good grades,' a specific goal would be, 'I aim to achieve at least an A in my mathematics course by the end of the semester.'