ANSWER - The ability to communicate with spirits is pretty universal. Some mediums will set themselves up as having special powers known only to a select few but the reason most people do not communicate with spirits is not down to the fact that they are unable but down to the fact that they haven't tried.
Effective spirit communication involves allowing your mind to take a rest from the distractions of the mundane world. The candles, incense and mood music are not for the benefit of the spirits, they are for the benefit of the person wishing to make the contact. Such tried and tested methods may seem trite and a touch Hollywood but they do help to make a delineation between the everyday world and the rested head space which is necessary to hear those in the otherworld.
The methods used may vary on preference. Specific tools like a pendulum or a ouija board can be helpful but the simplest way to make contact with a spirit is by direct speech. This can be verbal speech or telepathic speech (spoken inside the mind). The skill is not the ability to initiate the contact but the ability to hear the response and if necessary to be able to interpret that response. Some people are lucky enough to hear direct speech from a spirit, others sense their presence or gauge the connection with the spirit by another sense, perhaps by experiencing a sudden sense of cold of noticing an unusual smell. The expectation that the experience will follow an expected pattern will close your mind to the many ways in which a spirit may communicate back to you. So try to have no expectations and go into it with an open mind.