Freehand sketching is a quick and proficient way of putting ideas on paper. Drawing with our hand free of tools promotes the thinking process because we are completely absorbed in the details of the object we are drawing and nothing else.

With the increased use of computer aided drafting (CAD), freehand sketching will be utilized increasingly. Although design and layout can be done on the computer, we often want to get our thoughts sorted out and “on paper” before we begin a drawing.

The content of the freehand sketch relates directly to the formal drawing because all the information will be utilized, drawn with correct line values and dimensions and notation.

Grid paper allows us to keep our sketches relatively neat and proportional. 

The sketches will be neat because the grid-lines can be used as guidelines, and proportional because we can assign a value or distance to each grid.

A typical value to assign to a 1/4" grid when drawing a house would be 24" OR 2'
(This would be 1/8"=1'-0" or a relative scale of 1:96)

Grid paper can either be very light lines (which will barely photocopy) or heavy lines behind a sheet of paper and traced over.

Below is an example of a sketch done on grid paper.

Grid paper can also be used to draw irregular shapes.
See textbook page 30

Using projection lines helps us to keep our views lined up and project features from one view into another view in the correct location.

One very useful projection line is the miter Line 
at 45 degrees. It helps us to get information from the top view to the side view.

You can see examples of projection lines and miter lines in the sample above.

Linetypes should also be applied in sketches, especially object, center, and hidden lines.