Learn how to use the three types of Sketchup Inferences in this Sketchup tutorial. Lock an inference to allow reference to another point in your model. Reference multiple inference points to locate the intersection of the two.
SketchUp for Woodworkers Guide - SketchUp Tutorial
Prior to SketchUp, I just made designs with pencil and paper and a couple of general computer applications that were not intended for furniture design. I felt constrained, and the limitations of the tools were negatively affecting my designs. I wanted t