If you are using a star-finder (planisphere, star wheel,) you put the current hour on the inner wheel next to the current date on the outer wheel, and hold it over your head with the outer rim in the window pointing south. Now, the constellations on the map correspond to what is up in the sky above you.

Generally, star maps are designed to be used when held overhead. If you put the map down on the table with the top pointing north, the stars on the left of the map will be on the right in the sky. You can still use it this way, but be aware of what is happening. The ones in the magazines are printed this way, too.