How to draw electrical diagrams

You can create a drawing using the File - New menu command or the icon
Choose the size of the drawing and set it in the print settings and page size dialogues.
insert title block (if not already inserted) using command program settings (F12 - title block)
if you will need multiple layers, prepare them in the Layers panel a name them accordingly to their intended use
if you want to use a scanned floor plan, insert it in the lower layer
for the coarse objects placement start with snap 10 mm and decrease it when needed
insert the symbols and other objects and place them to their final positions. Leave some space at the edges of the drawing to allow for the possibility of printing on a different printer.
Before you draw connections (wires), make sure that the symbols are properly placed (at least the most important ones). It is possible to move symbols with wires attached to them, but only for short distances. The shift of already wired symbols may break their connections.
Use the s key to switch to the wires drawing mode and start drawing wires. Start with the major wires crossing the entire length of the drawing. If any connection was started the wrong way and you are not able to continue, you can cancel the latest diversion by pressing the backspace key. You can end a connection in the air by pressing the right mouse button.
you can use the function Outputs - List of wires to verify all wires have been attached correctly
make sure no texts, symbols nor wires overlap