It's going to depend on what kind of spiders you have, but in general an arisolized spider poison applied sprayed every 3 to 6 months should do the job. I had a bad wolf spider infestation in my house when I moved in so I bought a tank sprayer and some D-Fence SC. Just spray along every exterior entryway into your house and problem areas/corners inside and you should be good. If you wanted to go overboard you could also spray some Insecticide growth regulator but ive never needed to here.