If you are tempted to do your own tattoo drawings then all you need to do is look on the Internet. There are many websites that will walk you through each step of the design process. Whether it's a tribal design, eagle design, or your very own unique design there are many great examples to choose from and to get inspiration from.
I recommend that you start off by practicing to draw easy and simple tattoos and work your way up to the more difficult and intricate designs. It is always easier to come up with ideas for your tattoo drawings when you have an idea in mind so make sure you look at plenty of different templates before you get started. Focusing on one niche of templates to begin with would also be a great idea as this will allow you to get better and better at doing your own designs. There are also websites where you can watch video's of designers so you can see where they started and how they got to the completed design. This is great if you are a more visual artist and need some inspiration.
A great way to start your design is to just doodle until you begin to get something that you like, then do an outline of it, and add some more detail. If you are doing more than just pencil sketching you can also add some color at this point to really give your tattoo drawings some life.
Some artists that start out drawing their own tattoo end up drawing some for friends and then go from there to selling them online on various auction sites or even to local tattoo parlors. The great thing is that not many people are doing them on computers; tattoo drawings have stayed true to their heritage and are still mostly drawn by hand so your personal style won't be duplicated in mass volume by a machine. Even at the big tattoo parlors you see on the TV shows still do up a hand drawn mock-up of the artwork from a design that the person wanting the tattoo has done up.
If you aren't artistic in nature then your best plan would be to visit the same websites that show you how to draw your own design and print out their tattoo drawings and take them with you to the artist at their shop and have them create you a unique design. Some websites do you charge you for their templates but there are also free websites if you search hard enough. Or you can even take two or three designs and have them combine features that you like from each one so that you end up with a truly unique design.