When I first got my guitar, I meditated on the intro to the song "Kryptonite" by Three Doors Down which forced me into getting my chord switching correctly. I practiced it until I could do it flawlessly and then eventually the entire song (which I didn't really get to immediately since I was really just focused on the intro).

Anyways, I'm trying to get my legato skills down as much as my chord switching and alternate picking (which the intro to Sweet Child O' Mine has forced me to get down and now I do it religously on the Blues Pentatonic Scale to keep it at second nature).

Also, I've read an article from ZeGuitarist about using my pinky and now I do that religously along w/ the Blues Pentatonic Scale to keep playing in position going at second nature as well.

The reason I'm making this post is what I said previously is really all of the progress I've made and I need a new song to meditate on that will get me to get my legato down. The hardest song I could do is Smells Like Teen Spirit according to the highest rated tab on this website.

Any suggestions?
I've gotten a lot of LOLs in my time but I choose not to sig them to not look like a pretentious douchebag

practice? i don't really know what you're asking other than "how do i get better legato" the answer to virtually question of "how do i do this good on the guitar" is practice. lots of it.