How to Put a Flag on a Pole with Rope: Measure the flagpole and multiply the height by 2. Add 3 feet for knots and clips. Cut the rope to this length. Tie a clip or hook to one end and thread it through the grommets on the flag, starting at the bottom. Secure the clip to the rope near the top. Tie a slip knot in the other end of the rope and place it over the top of the pole. Pull the rope to raise the flag, then secure the slip knot to the pole with a clove hitch.