You can create a callout from a plan, section, or elevation view and then add detail components while using the model geometry as a base. When you create a callout or section detail, you can reference another detail or drafting view in the project.
The following is a general procedure for creating a callout or section detail from a Revit LT view. Your design intentions may differ. You can also use this procedure for imported drawings. See Import/Link Overview.
Model elements in the callout view display in halftone, allowing you to visually see the difference between the model geometry and added detail components. (See Halftone/Underlay.)
Sample callout with halftone roof, ceiling, and wall for background
As you sketch lines, the cursor snaps to the model geometry in that view.
You might create a region to show concrete, grass, or sealant. As you sketch the lines for the region, you can change the line style on the Properties Palette by selecting a different value for the Subcategory property. For example, you might want the region boundary to have invisible lines.