There is a simple reason why most people generally cannot tell the difference between astrology, palmistry and psychic services. They never had the opportunity to be educated in it. Most people just never see themselves trying to read up in order to know more about these subjects. So they never get the best of astrology or the astrologers. Thus people don't know enough to talk about astrology yet they can't stop NOT talking about what little they know about it. Well no more. By the time you go through this article, you should be in a better position to relate to an astrologer more effectively.
To begin with, every astrologer needs to have the following minimum data: your sex at birth date birth time and birth place. Any astrologer doing your birth chart without these would not be doing astrology. It's just the basics. It's astrology. With palmistry you offer your palm. With astrology you offer your birth particulars. If your astrologer doesn't ask for them then he might be using some other model for his predictions but it won't be astrology. He might even be pretending. Also the sad part is if you don't have this data then don't go to astrologers. Go to a psychic or some other diviner using other models for their prediction. So do you have your birth data? Check this out first before you even search for an astrologer. And you should have them as reliable as possible because the honest astrologer's work will only be as reliable as the data that you provide him to work with.
The basic idea of needing your birth particulars is because he needs to calculate the astronomical positions for the time that you were born. How did the galaxy look like? That is what the horoscope is about. So the astrologer uses the birth particulars so that he is able to see the configuration of the planets in the zodiac during the precise moment of birth. Astrology uses the picture of the galaxy at your moment of birth as its model to make predictions. Candle-reading diviners use the "configurations" of the melting wax of the burning candle to "see" the things that they interpret into their predictions tea readers see how the tea leaves position themselves at the bottom of your cup to make their predictions and astrology uses the galactic configuration of the planetary bodies for its predictions. So imagine what happens when your astrologer does not get reliable birth particulars to work with? He simply does not get to see the accurate picture of the galactic configuration during the subject's actual birth moment and he simply would not be able to reliably relate what he sees to your true life experiences. So what do you want to do? You want your birth particulars (especially your birth time) as correctly possible.
Now one of the most riveting things in any personal horoscope is what we call the Ascendant. This is the precise degree in the chart that is the "moment of physical birth" based on the time and place of birth you provide. So aside from accurate birth time you want to give the accurate place of birth as well. So the place of birth should be as accurate as possible as well. Knowing the town will do. But if the town is not on the map then give the closest town on the map in order for the astrologer to obtain the latitude and longitude of the birth place. That's why he needs to know the town in the first place. But if you can give him the latitude and longitude of your birth place straight away he won't complain.
What happens if you don't even know your birth date? Then really don't go to an astrologer unless you're ready to go a lengthy process called Birth Rectification. That might take hours if not weeks plus a lot of interaction with you to confirm your most likely chart. What the diligent astrologer (difficult to find them for free) would have to do is to keep on fine-tuning some of your horoscopic positions. He would probably start by placing your ascendant somewhere he thinks relevant and with that he'd try to read the chart as a whole and see if it fits with your life events. If it doesn't or he thinks it's not conclusive enough he'd continue adjusting the chart with other "what if" positions. This part of the work is so specialized that some astrologers offer this service only to other professional astrologers who need this work done for their very important clients.
About the author: Dr Agni has been using astrology for 37 years and has taught astrology for free since 1986, every week, till today. He is adviser to the Institute of Astrological Science, Malaysia, with its website at http://astrologyuniversitymalaysia.com