I edit several .tex documents I'm working on in TeXShop and every time I open them, I see Helvetica 12. Even with reading glasses it's hard for me to see so I select all, type Command-K, and set the font size to 18. I've tried TeXShop preferences "Set" but all it does is show me a sample of the font. The .pdf windows are just fine but
How do I set the default font in the .tex editing window?