Dust is mainly made up of human dead skin cells amongst other things such as pet bits and pollen. Have a good mat at your front door to help prevent outside dirty bits from coming in. Place microfibre cloths around the house for a quick dust. When doing a bigger dust start at the ceiling and moving down, use a feather duster at high level and a damp cloth where you can reach. Keep dust at bay and do it at least once a week if not more. Basically anything and everything in your home that has a surface needs to be dusted.