I have almost finished the splash deck around my 24ft pool and now am in the process of building an add on section to tie it to my pre-existing deck. Now although I am not physically connecting the two the add-on will run up near and actually a bit under the splash deck. My question is I have about an 18" or 19" step up from one to the other what is the best way to build a step or steps if you think that is best? What should I build them out of and also how should I attatch them either to the splash or to the pre-existing deck? Now I built the splash and left the railing off 3 sections and I intend to make the step the span of atleast 2 sections going down to the pre-existing deck. Please help if this all makes sense

In this case I think you would be best build the steps in the form of a box step. The following link will take you to the instructions for building them.

deckplans.com/howtobuild/stairs/boxstep01.html

As far as the building material. Build the steps to match the rest of your deck.

Deckman