Sage Bundle Stick is approx 12.5cm. 
My Personal Method: 
You start by setting your intention, ie. To clear the space of anything that does not serve your highest good, light your Sage Bundle Stick and walk room to room as you go, paying particular attention to any corners or dark places where you may "feel" that the energy is heavier or may be trapped and make your way through the house. You then douse your smudge stick either in salt, Earth or sand. Open windows and doors to create airflow and release the smoke and any energies you have cleared.