The priority should be your overall 800 score. That said, familiarize yourself with IR since it is the section that comes before the all-important Verbal and Quant sections. If you get frustrated in this section, it can affect you emotionally on the next two parts of the exam - which matter more.
The most common IR questions are two-part analysis (TPA) - typically 4 questions.
Then you'll see Multi-source Reasoning (MSR) - typically 3.
Graphics Interpretation (GI) - typically 3
Table Analysis - typically 2.
Here's more information about the IR section in the
IR Practice Pill