I've been playing alot of my favorite riffs lately and even inventing my own. I've been playing tons and practicing alot and I even named my guitar killer.

after learning the enter sandman part (what guitars do they use?) I begun to go after sweet child o mine, the chorus riff, the one slash plays.

I found a bunch of ways to play this thing but I"m not sure which one.

Should I finger the first 3 frets like an A major chord? and then switch my pinky to fret 15? It seems to be the fastest way to pick up the very first part. Or is there another way to do it? I'm way faster this way.

any help is appreciated, I basicly got the idea in my head now that you learn chords because they have certain shapes that can be applied to writing awsome riffs like these...