Some tips that i know of
1) Strange smells
One of my friends when he was a kid always complained of burn flesh
smell when others near him could not pick it up. When great
misfortune fell on his family Finally a holy priest came to his
house he pointed out that the house is "unclean" and rituals need
to be done.
2) flickering lights as ghost presence creates an interference in
electrical appliances
A widely known fact of ghost hunters.When lights and lamp posts
start to flicker, a "presence" is indicated"
3) sudden changes in temperature and magnetic orientation
As ghost presence noted by researchers can cause a sudden drop in
temperature and changes in magnetic field as ghosts are said to be
from a different dimension from ours when they cross over to our
plane, a disturbance is cause due to the different nature of
physics in our world
4) sudden blackouts or "white noise" for brief seconds on TV
This usually is caused by ghosts who get attracted to electrical
signals. As their presence is believed to cause a disturbance to
normal functioning of electrical appliances
5) Goosebumps and chills
Mainly psychological when your brain senses abnormal psychic waves
of ghosts which it is not used to. And as a result cause some
strange bodily sensations to occur
6) Strange behavious of your pets especially dogs, cats, parrots
and hamsters
It is often believed that animals can sense abnormal presences and
sensations . It is often noted that animals could realise before
hand of a potential natural disasters. Dogs have been especially
known to have the ability to "read" their human owners minds.
7) When objects get misplaced or lost for no apparent reason
Widely believed as a trait of a category of ghosts called
"poltergeists". These sprits had been known to do mischief on
humans
