1- Correctly assess your competition and what they are doing to market their businesses. You have to offer your clients something that is fresh and different if you want to get their attention.( You can offer free information on keeping your clients area clean - this will show your clients that you are an expert in your field).
2-Survey your potential market beforehand so that you can establish what your clients are missing in their current needs as consumers. You will want to know what they want and give it to them.( may be they need special cleaning product or prefer more special services)
3-Learn what types of advertisements work best in your business