Upon finding all the values, such as amp, the period and any shifts, how would i know how to graph the actual graph, and more importantly, to scale the horizontal axis?

The main point you have to stick to in order to solve this task is to divide given period by four and space out all the given points. Here is a picture which will make it absolutely clear.
You can see that in this pic we add the pi/8, accodrding to the basic graph of sine and cosine.
I bet this points will help you! Regards.