For
best results, make large scale changes at coarser (lower-numbered)
levels and small-scale changes at finer levels.
To
line up vertices, rotate an edge in the camera plane while approximating
it to be tangent to the surface.
To
remove standard mode edits (transformations) on a vertex, select
the vertex and press the Delete key. This does not actually remove
the vertex, but moves it back to its original position.