The sage and palo santo come in smudge sticks and sprays and they all do the same thing. They clear negative energy from spaces. They both have lovely smells so you can pick which one you want to use based on your mood and whether or not you feel like using the smoke or the spray. When you use the stick, light it on fire then blow on it gently to extinguish the flame so it will let off smoke. Repeat as needed during your ceremony.
With either, walk around the walls of each room of the house smudging it by waving the smoke with your hand or a feather (or spraying), paying special attention to corners between walls and the corners where the walls meet the ceilings. Open windows and doors as guided to release that energy from your space (I find I’m guided to do that more in nice weather than in bad weather). You can speak or think your intentions of releasing the negative and inviting only positive. You can also smudge any areas that feel like they need a boost of light energy. Do this whenever you feel inclined (especially before and after hosting guests) and on the Full or New Moon.
I sometimes have a hard time lighting the sticks in such a way that they will smoke for very long and once overdid it so that I was setting off smoke alarms!