Sounds like you've got a good idea around what you want, just not the absolute specifics. This can actually be more beneficial: Find an artist in your area whose style/portfolio you like (traditional, neo-traditional, photo-realistic, etc). Once you find one, schedule a consult, bring in your sketch, ideas, and any other example images you can find that have aspects you enjoy and talk with the artist.
They'll work with you to help implement a design that will look good in tattoo form (some images on paper/screen don't translate exactly the same into tattoo form well), take your deposit, and present you a stencil of the design the day of your scheduled tattoo. You can make any final alterations then if needed, then you're ready to go!
Good luck, let us know how it turns out!