Abstract or non-verbal reasoning is different from other reasoning type questions because it involves reasoning to do with images. While abstract reasoning is not as 'hard' as people think it to be, it is different as images comprise of a number of different components such as:
All of these need to be evaluated in the context finding the "pattern that exists" to then get to the answer.
As an overall process for every reasoning question there are 2 overarching steps you need to take:
This is a process I encourage you to take:

There are different approaches to take for each type of abstract or non-verbal reasoning question. Why? Because each one has unique requirements and having a customized approach for each one means you can move more quickly through the exam.
What are the pitfalls when it comes to abstract reasoning exams with a time limit?
The key thing to remember with abstract reasoning is that the pattern is already there - your job is to uncover it. It's not to come up with new patterns – it's to discover an existing pattern.
Now it's time to do your assignment.