The word cool has meant a lot of things over the course of history with all things having been considered and taken into account. The current meaning can be taken in two ways. You would either end up using cool as a signifier of temperature or you might just use it to signify that someone is really appealing in terms of social norms and the like. Looking cool is something that you would be quite eager to do, especially if you are about to ride on a party bus at some point or another. As a result of the fact that this is the case, you should look into things like wearing sunglasses since they are arguably the coolest kinds of accessories that you can put on your face.
Anyone that wears sunglasses is going to immediately look like they are always calm and in control. This is partly what you might want people thinking about you at this current point in time, and if you wear sunglasses then the various people on the Attica party bus are going to look at you and think that they should have worn sunglasses themselves because of how cool you look.
There are a lot of other reasons for wanting to wear sunglasses as well. For example, you might want to avoid the sun getting in your eyes. Alternatively you would want your eyes to be shielded from others since you are uncomfortable with eye contact in a lot of ways. Regardless of what the reason behind it is, wearing sunglasses is absolutely essential if you want to look your best on a party bus and you can experiment with different kinds of colors as well.