The term interdisciplinary artist is very broad and can mean many different things to many different people. There is also a distinction between becoming an artist and being a great artist. Anyone can improve his or her art skills or become an artist, but only those born with natural ability complemented by an extreme work ethic can become great in the world of art. If you want to become an interdisciplinary artist, it is important to be educated in many disciplines and routinely practice your techniques.
Art, in a loose definition, is expression through actions or creations. It is a very subjective thing, able to be seen wherever a willing eye lies. It's easy to see why art can cross into many disciplines beyond those typically recognized. If you aspire to become an interdisciplinary artist, you need to be able to manifest your artwork into multiple fields. A painter, for example, may also be able to sculpt or write plays.
Being great at such greatly varying things seems impossible. Fortunately, creativity usually finds ways to creep into everything someone does. An individual predisposed to become a great artist could find that his or her abilities transverse many disciplines. Also in favor of someone who wants to become an interdisciplinary artist is the fact that it does not mean you need to be the next Da Vinci. Anyone with a desire and passion for self-expression is an artist in his or her own right.
To become an interdisciplinary artist, you simply need to create work across many mediums. This can include physical artwork, like painting a canvas, creating a sculpture, or finding a picture. It could also refer to writing a poem or play or finding a new way of expressing yourself. In a sense, anyone creating art in more than one discipline has already become an interdisciplinary artist.
While some artists focus on breaking ground with their techniques, others are more driven to simply improve. Improving your artistic abilities is similar to improving in anything else. Not everyone is born great at art, but everyone holds the ability to maximize artistic potential. Taking courses in artistic techniques or other aspects of art education is one way to do so.
"Practice makes perfect" is something you might hear at a Little League baseball game, but it is surprisingly universal. Practicing different types of art is one of the most surefire ways to improve abilities. Not everyone will be a famous artist, but anyone with a genuine desire can become an interdisciplinary artist.