An intuitive explanation for LR grammars?
A language is $LR(k)$ if looking at the right side of a production, and looking $k$ symbols ahead, one can determine the left hand side of the production. This is quite incomplete, but intuitively easy (hah!) to grasp. In particular, it explains why $LR$ grammars are a much richer set than the $LL$ ones.

In practice, it is probably much more relevant to be able to understand the format in which your preferred LR parser generator spits out item sets when tickled the right way, and in particular how to track down the origin of conflicts and alternative ways to solve them (and their consecuences). I like the bison manual a lot in this regard.