A question about Mapping out Tattoos for a sleeve

I'm really wanting a tattoo soon and all together I'm considering a quarter sleeve and maybe half of a chest piece. I'm not exactly sure where I should get my first one or anything to be just right for the whole grand scheme of things. The best way that I can describe what I want is something similar to CM Punk's layout. A bunch of Random little tattoos, with one Big one in the background tying it all together.

Is there a certain way I should approach it? Like Mapping out exactly what I want, and where exactly I want every single little tattoo? I just don't understand how to make sure everything is in the right spot before it's too late.

If you could help in someway/anyway,it'd be greatly appreciated!

Please and thank you!