The truth is that there are guides out there that are bad. But I am not here to talk about those. We will assume that the guide you have is a good one. The best ones are made as addons which you use in-game. While they are pretty easy to install and use, some people still have trouble with them. So here is how you use a WoW Alliance leveling guide.
Installing The Guide
Since it is an addon, you will have to install it. Much like any software out there, they have a Setup.exe that you can use. You just follow the on-screen directions and it should install in no time. Just make sure that you put it in the right place on your computer by using the "Browse" option when you get the installation destination dialogue.
Using The Guide In-Game
As soon as you start the game with the guide installed, you will see the interface. Normally you can adjust this to suit your own needs. You can make the steps show you a lot more information, this takes up more screen space, or simple instructions which take less space on your screen.
Put the directional arrow somewhere where you can see it without having to look for it on your screen with your eyes. A good place for it to be is in the center of your screen, right above the quickbars. That way you will always see it and won't have to stop to see where it points you.
As you reach a quest objective, pay attention to the directions on your guide interface. They will update once you need to start killing NPCs or when you need to pick up something. In order for it to be more effective, set the guide to show you a few steps in advance. That way you will be able to organize yourself better.
If the guide stops working, or you notice a glitch, disabling and re-enabling usually fixes it. Once you got used to the interface, it should be real easy to level up your character. If the WoW Alliance leveling guide you have doesn't have the things you saw mentioned here, then you don't need it. You should only use WoW guides that can be used in-game. It is faster.
