There are many methods for reading research articles. The main things to know are:
Here's a graphic showing one common method for reading research articles.
![flowchart of a method for reading research articles](https://libapps.s3.amazonaws.com/accounts/95620/images/how_to_read_scientific_research_articles__flowchart.jpg)
For further guidance on reading research articles...
And just for fun... Types of Scientific Paper, from XKCD