Analogies are part of the aptitude test that many people have a hard time with. It is the most subjective part of the assessment, because different people can have different interpretations of language. What is a logical analogy for one person does not make sense for another. It is therefore important to practice a lot with analogies to recognize the most common patterns.
We have worked out some common patterns, it is useful to review them before you start practicing. This way you know how to solve the problems and you will make less mistakes!