Fibonacci Arcs are displayed by first drawing a trendline between two extreme points, for example, a trough and opposing peak The arcs are drawn, centered on the second extreme point, so they intersect the trendline at the Fibonacci levels specified. The interpretation of Fibonacci Arcs involves anticipating support and resistance as prices approach the arcs. A common technique is to display both Fibonacci Arcs and Fibonacci Fan Lines and to anticipate support/resistance at the points where the Fibonacci studies cross. Note that the points where the Arcs cross the price data will vary depending on the scaling of the chart, because the Arcs are drawn so that they are circular relative to the computer screen.
Above is a 3-Minute Bar Chart of Cisco (CSCO). The Fibonacci Arcs are drawn with the colors and levels specified in the preferences below.