Signature in Windows 8 Mail editable?

Hi all,

I have just upgraded to Windows 8 on a new HP desktop and still trying to find my way around it but I have managed to get to the point of finding where to include a signature in my emails but pretty disappointed that I cannot add my company logo or change the font style or size....I am hoping someone can tell me there is a way because it can't possibly be that boring. I am forever cutting and pasting a signature from Word which makes sending a quick email unachievable. I'd really appreciate any help. Thanks