First you need to prepare and sterelize your cicrle, spirits will not come unless you show them the right respect, and nothing better than being clean. Light a white candle and walk the outer-ring of the círculo calling on the elements and if you wish, light a stick of incence. There are two ways you can try, Ouija or Scrying.
Ouija - if you don't have a ouija board, you can cut squares of paper, one for each letter of the alphabet, 1-10, and yes and no answers. Arrange them in a círculo and use a glass as the pointer. Then all you have to do is ask if any spirits wish to make contact and go from there.
Scrying - sitting in front of a mirror or a clear bowl of water. You have to concentrate very hard for this as you need to 'open' the mirror into the other world a bit like a doorway so the spirits are able to come through. Then all you do is talk to the spirits through the water/mirror like an everyday conversation with another person. However you need the atmposphere to be very quiet, so no ticking clocks or buzzing of the computer, no background música as these can all make your concentration waver and also make it mais difficult to hear the spirit. You need any mais help or step-by-step instructions just message me :)
^ no they won't. Spirits are unable to harm anyone due to the lack of a metabolism. Pure science. However they can mover certain object providing it's not too heavy, but they soon tire and go back to the netherworld. If you're having problems with a spirit it's mais likely a poltergiest but they don't come for callings, they haunt a certain place and remain there until a luckless victim comes around so they can pull pranks. Spirits are completely harmless, you just need to know how to handle them and you can only know that if you gain the experience.
Go to a graveyard, and play 'Never Gonna Give You Up' at 2:00 A.M. in the morning continuously. That will get them really pissed, causing them to come out from hiding. When they're out, spray deodorant in their eyes, while cantar 'Look At Me Now', and they'll get so mad, they'll commit suicide twice.