How do you start out an research paper?

my research paper is about mental retardation but I don't know how to start it off.

I order to craft an effective research paper, you need to narrow the subject matter and choose a question that the paper would answer. What about mental retardation? The field itself is too broad for a paper. Focus on one aspect and direct your research toward answering that question.

First thing you want to do is develop a thesis. Do some reading or think about the subject and what aspect about it that interests you the most and develop a common theme for your paper.

Then once you decide the direction that you want to take the paper, you can start getting resources and research together and go from there. Good luck.

i dont know i started out on a planet but only a few people i met dont want to turn it into a research paper with some cave man technology

What are you going to research?
Mental retardation is a very broad topic.
Define your thesis:
Some possible ideas:
The prevalence of mental retardation in the inner cities. (then you could talk about lead poisoning in old housing, of premature birth due to young mothers, of drug and alcohol abuse and how it causes mental retardation, and compare the rates of mr in poor people in the cities versus wealthier people in the suburbs)
Or:
Mental retardation and fetal alcohol syndrome
Mental retardation and birth defects
Mental retardation and the public school special education

See what I mean? You need to narrow down the topic!