Watch out for your own bias! Do not eliminate relevant information if you think it disproves your hypothesis. Try to balance your arguments.
One important thing to be aware of is bias. There is bias in almost everything you read. Authors try to convince you that their point of view is the best one out there. Depending upon the topic, there are differing levels of bias. Topics like abortion, religion, animal rights and politics lend themselves to bias. Here are some factors that will determine the degree of bias in your source: