We can’t stress this enough: identify each strut with a color. Use spray paint or anything that won’t rub off or come off easily, at least until you finish putting the geodesic dome together.
Many lengths have little variance between them and that can easily lead to grabbing the wrong one. Proper identification takes little time and you avoid future headaches!
Below is a color coding chart for struts. These colors correspond to the assembly diagrams on each geodesic calculator pages on Domerama. In other words each letter always has the same color regardless of the dome you build. One chart is good for all.
Click on the image below to view a larger version of the color chart