That's the hardest thing. We spent a long time landing on it when we did our renovation. Had color chips in the water at different depths for days and days. It will probably be easier if you make the big choices first and then focus on the small stuff...What I mean is, pick the foundation of the color palate that you want. In our case it was:
Blue Pebble Finish (Not Green,Grey or Black, and not smooth)
Dark Blue Coping Tiles
Light/White Pavers
Once you get the basics of the combo you're looking for, fine tuning for the choices gets a little easier.
That still left us with lots to figure out (so still not easy)
-Which blue? Add the glass beads for more pop?
-Big Tiles? Small Tiles? What color Blue?
-Color, size, lay pattern?
Lastly, if you're getting a troweled on finish don't freak out when it's first put on and you add water. The water needs to be stabilized and you need to brush like mad for weeks before you actually get to see the finished product!
Don't forget to post pics!