Work to prevent the kinds of conditions that cockroaches love. They enjoy dirty, greasy areas with plenty of moisture. The kitchen is one place that could see a lot of cockroach activity, so it needs a regular, thorough cleaning. Areas to include are behind and underneath appliances (even the big ones), kitchen cabinets and under the sink. Try to place food in tightly sealed containers, don’t leave pet food out for too long and have a tight lid on the trash can. Remember too that cockroaches usually avoid well lit places so it might be worthwhile to leave a few lights on a night.
Its not only the kitchen that cockroaches can be found, other areas of the home such as the bathroom provide a suitable environment. Again, keep the bathroom very clean and as dry as is possible. Go through the home and look for any leaking pipes or dripping taps and fix them immediately. Cockroaches will be drawn to these kinds of area. Also, if you observe any places that could be points of entry, have them sealed up.
It may reach a point where the cockroach infestation is too bad to handle. This is time to call in a professional pest control specialist who will treat the problem in the right way. However, placing boric acid in areas of previous cockroach activity should help to control them afterwards.