One of the most popular software packages in the world, Solidworks is used extensively by engineers to model and design products. This software is not only used for engineering purposes, but also for 3D printing.
The first step to enable 3D sketch is choosing Edit Sketching mode by selecting File > Sketching > Edit Sketch. After that, it's time to start drawing. With this mode activated, you will be able to draw lines by moving your mouse cursor around on the screen. To do so, hold down the left mouse button and drag your mouse pointer around on the screen until you have a desired shape or object being sketched out on paper with an arrow through it.
The next step is transforming the sketched-out object into a series of lines using Measurements Toolbox > Create