How can i detect ghosts or spirits without additional gadgets?

i want to detect ghosts without any additional gadgets or devices coz i think i have a ghost in my house coz at night i hear sounds as if somebody is knocking just behind the bed hood,toilets start to flush on their own and the scariest part is one night i felt as if somebody is at the foot of the bed i also felt its hand touch my foot.anyone please help if you can!