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Draw constantly. Draw on contoured objects. Test your tattooist skills with a non-toxic marker and a friend. Use henna to learn how to apply designs to the contours of the body. Train yourself in inking lines and tracing.
As a professional tattoo artist, you'll be expected to sketch out, sometimes start to finish, the designs your clients want. This will require you to be skillful at reproducing many different kinds of styles, which can only really be mastered through experience and repetition. Work on transitioning from pencil to pen, which has a more permanent feel. Apples, oranges, and other contoured items, like rocks, can simulate some of the difficulties you'll have tattooing various parts of the body. Seek out items that somewhat resemble body parts commonly tattooed, so that you're well prepared when someone requests a tattoo on a more curvaceous part of the body. Alternatively, draw your designs at an angle, so they're in a certain perspective. Though the experience of drawing on a person's body is markedly different from operating a tattoo machine and depositing ink into the skin, this practice will get you accustomed to drawing on a living canvas and various body parts. You might even seek out your more ticklish friends so that you have experience with a squirming client. Henna is a kind of traditional dye that has been used since ancient times. It is relatively inexpensive, can be bought online or at many general retailers and pharmacies. Due to the fact that henna remains on the skin for several days, you might want to hold off trying this until you're somewhat practiced on inanimate objects. Then, following the directions on the package: Mix your henna dye and collect the applicator for your henna. Apply it to the skin of your practice subject in the design desired. Note any improvements that could be made and ask for feedback. Many professional tattooists first began learning the art by tracing sample tattoos and simplifying designs to be more translatable to the skin. This skill can be imitated and studied academically by enrolling in a class in Inking, which is the practice of outlining and interpreting an original pencil drawing.