A research team in Delhi is designing a randomized controlled trial to evaluate the efficacy of a novel antihypertensive drug versus standard therapy in 500 hypertensive patients over 12 months. During the protocol development phase, the statistician identifies that the study has 80% power to detect a clinically meaningful difference of 10 mmHg in systolic blood pressure between groups. However, the team realizes they have not yet decided on the method for allocating participants to treatment and control arms. What is the most appropriate next step in trial design?