This is a great article posted on another site (who reposted it from another site, who took it from another), but I thought many would enjoy it here. It is The Lazy Man’s Guide for Constructing a Call of the Cthulhu Adventure, written by Sandy Petersen, original author of the Call of Cthulhu.
A few musicians play their instruments and a beatiful maiden dances to the music. Wonderful to look upon, you surely will spend a few coppers, will you? In addition, two thieves move through the on-looking crowd. "Spare the coppers - loose the silvers!" your father used to say.