I have a sketch on paper that I would like to send to someone via email. What can I do to send it to them without changing the size of it and will still allow for them to print it back onto paper? Would this all be easier if I just sent it through the local post?
It sounds like you are concerned about keeping the scale the same?
It depends on who you are sending it to. For example, if you scan the drawing at 150dpi and then send it to someone who will print it out at home, that should work perfectly. Same thing with 300dpi for a high end printer. It is typically the dpi (dots-per-inch) or ppi (pixels-per-inch) that will change your scale, because your pixel size should always stay the same.
You will also want to make sure that when the recipient prints it out, they choose not to scale the image in their printer settings.