When building monuments in the cliffsides (and I tell ya guys, this one was a lifesaver for me!) hit H to show where the other tombs are already at so you can easier place them. And honestly, I only use the R for rotate and the H one. The rest of the time I use the overlays in the interface.
But Baltic is right. . . .check your manual. . . all should be in there
"To thine own self, be true"
-Shakespeare