You can eliminate many pollutants like dust and pet dander by careful household cleaning. Making sure your heating and air conditioning systems are well-maintained also helps remove pollutants before they reach your home, and cleaning air duct systems may be helpful in keeping your systems maintained.
You can decrease the concentration of indoor pollutants by increasing the quantity of air circulating. Open windows and doors, and use window or attic fans. Bathroom and kitchen exhaust fans move indoor pollutants out of the room, and increase the outdoor ventilation rate at the same time.
Well-maintained and efficient air cleaners can significantly lower the amount of pollutants in the air. Their usefulness varies considerably, depending on the type of cleaner (table-top models will probably be less effective than a whole-house system), and on the strength of the indoor pollution source.