When taking a bath or shower, use only very gentle cleansers. Don't scrub too hard. After you take a shower or a bath, pat your skin dry gently. Be sure to moisturize all over with a natural oil such as olive oil. This will help keep the moisture from your bath in your skin.
Instead of scratching, try using ice to cool itchy areas. You can get an inexpensive gel compress and keep it in the freezer. Take it out and hold it over itchy areas whenever you need to. Keep a dry washcloth in your purse or pocket at all times. If you become very itchy away from home, soak the cloth in cold water. Hold it over the itchy area.
Avoid feather pillows and opt for a pillow that is less likely to attract and keep dust mites. Foam pillows may be a better choice for you and you can also invest in pillowcases that help keep dust, dust mites and allergens from getting into the pillow in the first place.