Not everyone has the ability to draw or write accurately and neatly.
Guide lines can be used to help produce neat lettering when drawing. These lines are drawn as extremely light horizontal and vertical lines to regulate the height and width of lettering.
It is often difficult to erase these lines once the lettering is complete, so use a good hard pencil and draw the lines so that you can just see them.
Here's some examples of how to use guide lines to create neat lettering.
Lettering should be either vertical or sloped at an angle of 2:5.