"did it before but don't know how" how did you know you summoned a demon? did it tell you, or you got a feeling? in either case, you probably summoned it by mentally inviting it into your home. it's not really summoning, more likely it was passing by and saw your place, you didn't have a protection over your home and it came in for a while.
there are tons for demons, some more dangerous than others, i'd research to find out which one you need, how to call it forth, and how to send it away. i'd also cleanse and protect your home, energy is probably pooling and any being can enter without much issue.