Intros.

I am never quite sure how to play an intro before the singing starts. Some videos of cover versions i have watched seem to play it just like the original recording but i don't know how to do that unless you actually had the tabs of the intro i suppose.
I just end up playing the first line or two of chords but of course it sounds nothing like the original intro. Just wondered what others do if like me they can't read music. Hope this makes sense.