How long is the quote? I have used some letters that are about 1 inch tall in capitals. It said, "Best Dad Ever!" and had a picture. If there were no picture I could have used larger letters. It really depends on the look you want and how wide the lettering is.

I guess you go by your hoop size. I would make as large as possible. I was going to put "PARKVIEW" on a sweat shirt for my sweetie's grandson ,but was disappointed that the word was so long that I could not get the letters large enough to show up. I did not want to multi hoop so I gave up. I opted to use a large paw print instead.

If you are planning to put it symmetrically across the front, the whole thing needs to be as wide as you can get it! I'd use Embroidery Fonts Plus to do the design, arch it slightly and make it as wide as my hoop.

Do you want it large, across the middle of the sweatshirt, or like a monogram on the left chest?