Ensure your fats (usually butter or shortening) are cold. When these fats melt in the oven, they create steam, which helps the biscuits rise. Keep the buttermilk or liquid ingredients cold as well. Also, make sure your oven is fully preheated to the specified temperature before baking. A hot oven is crucial for the initial rise of the biscuits. Use a sharp biscuit cutter and press straight down without twisting to cut out the biscuits. Twisting the cutter can seal the edges and hinder rising.