Grab a small stockpot and fill it about 2/3 full of water. Add one sliced lemon, a few sprigs of rosemary, a few sprigs of dried lavender (you can add lavender buds instead) and 1-2 tsp of vanilla.
Let your mixture simmer all day long on the stove, adding water as needed. I found that you can use the same mixture for several days in a row. After that, its best to toss and start over with a new mixture.
Try it and wait for the complements on your wonderfully fragrant home!!