How do I get rid of roaches?

I live in an apartment and I must have someone that lives by me that has them because I saw one by my fireplace a couple of weeks ago and made my apartment come and spray. Then, I just took my dog out to go to the bathroom and I found one in my bed!!!! GROSS!!! I can call my apartment to come spray again, but it's apparently not working... what do I do??? I'm so disgusted!