Never, ever, ever, make your bed.

[xoxoxoBruce]

Preventive Strategies for Dust Mites
Use a dehumidifier or air conditioner to maintain relative humidity at about 50% or below.
Encase your mattress and pillows in dust-proof or allergen impermeable covers (available from specialty supply mail order companies, bedding and some department stores).
Wash all bedding and blankets once a week in hot water (at least 130 - 140°F) to kill dust mites. Non-washable bedding can be frozen overnight to kill dust mites.
Replace wool or feathered bedding with synthetic materials and traditional stuffed animals with washable ones.
If possible, replace wall-to-wall carpets in bedrooms with bare floors (linoleum, tile or wood) and remove fabric curtains and upholstered furniture.
Use a damp mop or rag to remove dust. Never use a dry cloth since this just stirs up mite allergens.
Use a vacuum cleaner with either a double-layered microfilter bag or a HEPA filter to trap allergens that pass through a vacuum's exhaust.
Wear a mask while vacuuming to avoid inhaling allergens, and stay out of the vacuumed area for 20 minutes to allow any dust and allergens to settle after vacuuming.

SOURCE: National Institute of Environmental Health Sciences - National Institutes of Health. Dust Mites..

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