Unfolding shapes are commonly used in diagrammatic reasoning tests. This means looking down on the 3-D shape to find its plan view.
For example, imagine we were standing directly above this shape which is on the floor. From this perspective you would see shape C which is the correct answer.
The trick is to first count the sides and visualize what each side looks like flat AND how they all fit together. This will help you visualize how the shape looks.
Some people can do this much more easily than others, but if you find it difficult, practice and watch your results improve.