In the Bedroom, Size Matters...
I recently had a client ask me about placing a rug in her master bedroom. She wanted some pointers for where the rug should lay, in relation to the bed and side tables. Luckily, standard-sized rugs usually work in the bedroom, since our bedroom furniture these days is mass-produced in similar sizes. So, here goes, in 3 easy steps:
The rug should come out a few inches past where your side tables are (think 2-4 inches in FRONT of the side tables)
The rug should go out past the side tables a few inches on either side
The rug should be past the foot of the bed a couple of feet. If you have something like a bench in front of your bed, the rug should still be able to fit the bench (all four legs) on it.

In the sketch above, you would use a 5x8 rug underneath a Queen bed, with small-medium side tables.