How to get a ringtone on iPhone?

I have an iPhone 4s (iOS 7) and I want to make a song (Berzerk - Eminem) my ringtone, I bought the track a while ago but I can't figure out how to make it my ringtone on my phone can someone please help me (and not tell me that the newer iPhones are better and worth buying coz I don't give a.

I have an iPhone 4s and here's how I make my own ringtones. I'm trying to keep it simple so hopefully you catch on.

-Download Ringtone Maker App by typing in "rmaker" in App store
-Open rmaker app and select your song of choice
-Use app to customize the 30 sec you want as your ringtone
-Hit the button that looks like a floppy with an arrow on the bottom right when you're happy with the 30 seconds
-Hit send when its created and email to yourself
-Save the ringtone from the email to the laptop that is the iPhone's default laptop (save in iTunes "automatically add" folder)
-Connect your iphone to your laptop and open itunes
-Go under "Tones" and drag and drop the tone into your phone
(if your tones automatically sync you won't have to do this)
-Then go into your iPhone's settings > sounds > ringtone > and select your ringtone!

That's all it takes! Once you get the hang of it you'll be making ringtones in a heartbeat. I don't know how easy that was to understand but if you have problems feel free to email me.