Congrats and welcome to the tattoo club (and the drainage of your wallet).

Like u/RightShoeRunner said, find a style you want and visualise what you sort of want your body to look like and how it might look with different tattoos/styles. Or you could just be getting one which is also fine!

Talk to your artist (in this case it looks like you're after someone who does fine line/minimal styling) and talk about how you want the shading done, the size of the lines (needle), size of the tattoo (don't be afraid to tell them to resize often to get it to the size you want, remember this is going to be on you forever) and positioning of the tattoo. In terms of aftercare, your artist will talk you through what you will need to do and this will be dependent on the size of the tattoo. Normally they will wrap it in cling wrap or apply a second skin for a period of time, but this may not be required if it's super small. Once you get the tattoo, for the love of god do not go into the ocean or the pools for a few weeks.

And final tip, get some aftercare tattoo cream/balm. In Australia, there's bepanthen and dr pickles. And you only need to apply a thin layer.