You can contact a paranormal researcher. Just conduct an internet search with "paranormal research" and a specific city or town to find contacts of researchers who live within your area. For you to get professional and reputable researchers, seek referrals for who have already had their houses investigated for paranormal activity.
You can make a ritual: all you need is turn off all the lights in your house and turn on a candle, then close your eyes and said: if is someone in my house turn off my candle many times if the candle still on there's nothing in your house but if it turn off.... (this work trust me)
Call me. In fact, I'll just go ahead and do it for free. My research finds that your house has no paranormal activity. In fact, there is no evidence that paranormal activity--that is activity that is not bound by the natural laws of physics--has ever existed. I know that's not very fun. Just tryin' to keep it real.