The reason why, those clients or boss or whoever wants to check your work will not print a full size hard copy just to check your work, right? They most probably print this out in an 11'x17'(Bsize) or 421mmx297mm (A3 size) paper size. Your symbol should be visible in a small print out like 11'x17'. It is like a font/text size, as I've said on the other forum topic. With regards to symbol sizes, it is on your own judgement what size do you want your symbol to be. 2nd is, inserting your symbol in the paper layout which you don't have to scale up or down you symbol. Which you need to scale up your symbols as per scale.
First is, insert your symbol in the model including the plot plan or floor plan. There are two type of inserting a symbol in the drawing.
