There are many myths associated with Buddhist Art so it is important to understand the purpose of creating it.

Buddhists use art as a Dharma instrument, not as an object d'art.  It shows us important teachings and the teacher who originated the teachings. Hands, jewelry and it's placement, clothing the style, color, etc; plants, objects and other people around the image are key elements.

Buddhists commission this art as a means to transmit dharma teaching. To create the art one need only have intention.  But to create good art you need some skills in the media and a sound understanding of Buddhist teachings and iconography.  There are plenty of books now to study symbols.