Male tattoos should always occupy surface of the muscles that’s being tattooed and need to follow anatomy of the muscles.
Female tattoos should follow the shape of a body.
When setting up a tattoo, it’s most important to:
Computer calligraphy is perfect. It can be printed in any size and can show any form of letter. Fact is, when client make a choice, they choose the amount of text, the font, the size, and the positioning on their body. What most people will end up with, if they’ve chosen wrong, is one pretty little stain. Font size should be 0.5 cm minimum in height for lowercase letters, and 1 cm for capital letters. Fact is, everything is technically doable, but a tattoo will expand in time, and will probably merge all the letters in one stain.
Calligraphy is a category of text, but it’s written by hand. It guarantees a better quality because tattoo artists will normally, by instinct, make you a size needed to last a lifetime.
If you want a face tattooed, and it’s not a portrait, size of the face needs to be a minimum of 3 cm.
Portrait should be a minimum of 8 cm.
Naturally, animals count here as well.
If you’re looking for at least a tiny dose of realism, size should be at least 8-10 cm. Below that is best to adapt by style: the lesser, the simpler.