you can either prune the growing tip, just cut off the main stem, just above the highest 'fork' ... or, a lot of people prefer to just 'train' your plant ... just keep bending it over, tying it down, if necessary ... if the stem is trained horizontally, new buds will form all along the length of the stem ... (marijuana obeys a receptor in the highest part of the plant, ...tying it down, or cutting off the highest point, allows for new growth along its length, where it is seeking the sun) ... hope that helps ... :smokin: