Do whatever works for you, as long as it sounds good and you stay in-time. When learning a new song, I often skip all the slides and hammers, then add that fancy stuff later after I have the basic song figured out. I used to think there was only one exact "right" way to do each song, which meant following the tabs exactly. I've since noticed that most people make little adjustments to the songs, which adds interest and make them unique. If you look up some of these bluegrass tunes on youtube, you'll find that no 2 musicians play the the songs identically.
