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Avoid signing with your initials or a monogram or people may not be able to identify you as the artist. Even if some people recognize your initials or monogram now, other people might not, and your painting could eventually become unidentifiable if your full or last name isn't on it. If people can't read your signature, they won't be able to identify you as the artist. It's true that some famous artists have illegible signatures, but they can get away with it because a lot of people in the art world are familiar with them. If your signature is illegible, future owners of your painting will have a hard time finding out who you are. Practice signing a legible signature on a piece of paper. Then, show a few friends and ask if they can read it. If they can't, work on making it easier to read. That way people will start to recognize your signature overtime, which will make your artwork easier to identify. If your signature is always different, people might not realize your paintings were made by the same artist. If you don't like the signature you've used in the past, come up with a new one now and use it on all your future paintings. A signature that is too bold can take away from the rest of your painting. Your signature should be noticeable enough that people looking for it can find it, but not so noticeable that it's the first thing people's eyes are drawn to. An easy way to make your signature blend in is to paint it using a color that appears a lot in your painting.
Sign your painting with your full name or last name. Use a signature that's easy to read. Use the same signature on all of your paintings. Avoid using an eye-catching signature.