Once you have established a clear perspective on your subject, be consistent and try to maintain it until you have exhausted everything you have to say about the subject. Do not switch: (a) between subjects, or (b) between points of view, or (c) between levels of discourse, or (d) between levels of diction unless you clearly indicate to your reader what you are going to do next. Otherwise, it can be very disorienting for your reader to follow along.
Create smooth transitions and logical connections between different ideas and different parts of your argument. Consider whether what you have just said is sufficient information to lead you to your next observation. Linking words like "because," "since," "while," "when," "as," "by," "by means of," "consequently," "as a result," "for this reason," "through," "thus," and "therefore" can be useful for drawing out relationships between ideas. Transitional sentences are necessary for connecting paragraphs. Do not continue your line of argument using demonstrative or personal pronouns ("this," "that," "these," "those," "it," "he," "she," "they") unless the antecedent has been well established.
Develop your thoughts as if you were answering a series of questions, moving from "what?" to "where and when?" to "who or by whom?" to "how?" and "why?." First of all, you need to explain what the phenomenon is that you are observing. Then, try to determine under what conditions the phenomeon is taking place and how exactly it manifests itself under these conditions. Decide what agency is involved: who might be controlling or promoting the phenomenon and who might be affected by it. Finally, you need to think about causality: why is the phenomenon taking place at this particular juncture and what purpose or function is it serving? You probably will not be able to answer all of these questions with every assignment you undertake, but you should at least be thinking about them.
Consider how you are saying relates to your overall argument. Some information you may find curious, interesting, or nice to know, but unless it is clearly relevant to the topic you have chosen, do not include it in your paper. You can always save it for another time.
Show your reader the different stages of thinking that led you to reach the conclusions you have made. Do not make your reader do the work of drawing connections and conclusions for himself or herself. That is your job.