Adding a Lay-by to an Alignment for Corridor & Template Drop

Hi,

I'm stuck on knowing how to add a layby to an alignment that I want to add a corridor and template drop to. The long term goal is to get cross sections of this area.

Does any one know how to do this or if there is a tutorial on this kind of thing?

I will continue to look myself but right now I am totally stumped on how to do this.

Josh