Not every source you have brought in will fit EXACTLY with your topic, so it is good to have a clear understanding and to communicate that knowledge to your audience. It also gives you a grounding “point” to come back to as you’re discussing your sources. Your very first sentence should communicate both your tone and agenda, demonstrating a clear focus for your discussion.
As part of your “introduction,” you want to address the field of research on a broader level – what type of studies are most common? Is there a geographic area that is driving the majority of the research or are there significant geographical variations? For example, you may want to discuss quantitative vs. qualitative trends, if it’s mostly longitudinal studies, surveys, focus group analyses, etc. Maybe you struggled to find relevant research but found many pilot studies, indicating that it’s an emerging field. These are all good things to note before you move on to talking about the articles or sources more specifically.
You want to make sure that you are not just describing the literature, however. Above and beyond all else, the purpose of the literature review is not simply to provide a “catalog” of sources with a brief description (in some fields, this is called a descriptive bibliography!) but rather to ensure that, in your own voice, you are comparing and contrasting the literature in a way that is fair, ethical, and holistic.
There should be resources both supportive of and in opposition to your position, and you should be working to show how they work together to build not just the reader’s but your own understanding of the current state of the field. This is important because, near the end, you should take care to identify gaps in the research, as well as where, if relevant within those gaps, your research is situated!
Ideally, your chosen research area had a very manageable scope that provided you with neither too many nor too few current sources. However, what should you do if that wasn’t the case? If you were required to broaden your scope a bit to include either less current articles, or less directly relevant articles, you will need to justify your inclusion of these sources.
If, on the other hand, your research area was very large and you simply weren’t able to reasonably narrow the topic, you will need to establish that you are presenting only a selection of the current research, and perhaps explain why there is so much happening in that area at the moment!
One thing to keep in mind is that although I’ve laid the process out as “step by step” with the writing coming last, you can, and should be, writing as you go. If as you’re reading articles, you make interesting observations or note something important, write it down immediately so that you can build around these elements. Remember that you can and should both criticize and praise articles; good articles might still have flaws! However, though you want to present a balanced perspective, focus on highlighting evidence that supports your position.