You use the same tools and procedures for sketching ramps that you use to sketch stairs. You can create ramps in a plan or 3D view by sketching the run of the ramp or by sketching boundary lines and riser lines. Just like stairs, you can define straight runs, L-shaped runs, U-shaped ramps, and spiral ramps. You can also modify the outside boundary of the ramp by modifying the sketch.
Finished ramp