If the ghost room is large, use thermometer to get approximate spawn point of the ghost. It glitches out showing negative temperature if a ghost passes by you. Once you have an idea where the ghost will materialize during the hunt, get at least three candles. Light two candles and place them where you think ghost will spawn and keep one lit in your hand if your failed to guess the spawn point. As you can see in the picture below, candle in players hand show how close both candles to Kupper to knock her down.

i tried but it doesnt work.I put one candle on the ground and one in my hand, the ghoust just walk through the candle on the ground and attack me.