Use cold butter. This is important to ensure that you end up with a nice, flaky biscuit.
Do not overknead. The heat of your hands will cause the butter to warm up- this makes the biscuits tough. And nobody likes tough biscuits.
Do not overbake. At my house, we prefer soft, tender, biscuits– not hockey-pucks. Therefore, always be sure to set your oven timer for several minutes less than the recipe calls for. I usually pull mine from the oven when the bottoms are golden brown. Generally, the tops are not brown. If you wait that long, you will usually end up with a crunchy hockey puck.
Buttermilk Alternative: Take 1 & 1/3 cups whole milk and 1 tbsp. vinegar OR lemon juice. By adding acid to the milk, it will curdle the milk and work with making the biscuits rise.