This is a great question that, unfortunately, cannot be answered in just a couple hundred words. There are important issues that focus on educating one's self prior to embarking on such a course of action, particularly the downsides of using steroids – the side effects, the proliferation of fake gear, getting off of them, getting blood work done, etc. And, the fact that buying, selling and transporting them is (in America) still a felony, not to mention banned by all sports federations. All very important salient issues that require a lot of space to do justice.
Despite all positive effects of doping on the body they could be dangerous. Possible side effects of anabolic steroids can be avoided by choosing the right form (oral or injectable) and combination as well as by taking reasonable androgenic dosages. It has to be mentioned, that the most side effects of drugs disappear after the cycle is completed. Moreover, many of them can be blocked during the cycle by using respective supplements. Therefore, in order to avoid possible negative consequences one shall pay attention to studying information about the drugs prior to use them.