Hey Chrisnew.
The first recommendation I have for you is to draw a diagram. To start off draw two parallel lines and then a few more than intersect these lines in some way.
@Chrisnew, Actually angles do not have "sides".
Definition: An ANGLE is the union of two rays with a common endpoint, called the vertex.
So two angles could have their rays parallel.
Do vertical angles have that property? Think about each point on a line is the endpoint of two rays opposite directions.
I encourage you to follow the advice in reply #2.