A quick go on the Elevation Tool.
You have 4 commands for the elevation tool
Addition - Raises elevation based on brush and feather size, by the speed of % strength.
Subtraction - Lowers elevation based on brush and feather size, by the speed of % strength.
Smoothing - Averages the difference between non equal elevations, by the speed of % strength.
Set Level - Sets the elevation to the level indicated in the elevation value field, based on bush and feathers size.
With the elevations tool selected, you can select the different commands using the shortcuts 1-4 for the left mouse button, and 5-8 for the right mouse button.
For finite control, set brush to 1, and feather to 0, toggle the wire frame on, and place the brush over the wire frame line intersections, to adjust one point at a time.
Use spline deformations (then bake), for more efficient ditch's, ramps (stairs), cliffs, rivers, creeks, and raised roads...ect.
This is just a quick go on the elevation tool. If bacon doesn't fry up some good grease videos, I'll be sure to get one done, but it will be a couple of weeks. Real life got me busy.