Applications :: Mail Text And Signature Fonts ?

Today, after using a signature in Apple Mail for the past few months, I discovered that my signature is HUGE when read by non Apple Mail users and that the text in my emails is in Times New Roman even though I set it to Helvectia by default.

Turns out this is a problem in Apple Mail, as setting a default font only affects what YOU see, not what the email recipient sees. This seems backwards to me. My emails have apparently been all unorganized for months now. I've sent out job applications thinking I had a sleek format...

Anyways, researching this, I read nearly every post in this google search, but still don't understand how to fix the problem. Apparently there's one "fix" involving stationary, and another fix where you begin typing right at the beginning of the sig...?

Can anyone tell me how to make my emails that I send from Apple Mail show up for my recipients in Helvectia and have the signature be in the same font size and Helvectia as well ? And no, clicking the "always match my default message font" button didn't do this, just in case.