When you look figuratively at the idea of making your attitude your ally, what you see is that it basically means that the attitude you show will be reflected in the path you take in life. In other words, your attitude will affect your life and help you determine what happens to you.
Let's break it down and see what "making your attitude your ally" really means in simple terms.
First, you have to define what an ally is. An ally is basically a path you walk. Your attitude is the way you act, think and treat those around you. Your attitude affects everything in your life. It greatly affects the way you think and the way others treat you.
Now, making your attitude your ally would mean letting your attitude guide you. Your attitude will shape everything in your life. You are going to travel the road that your attitude takes you.