What are you going after mid or high conductors? Old finds or recent drops? Relics, coins, or jewelry? What are the bottom "sand" conditions like? Trashy or not so trashy (non-ferrous, e.g., can slaw, pop tops, pull tabs, foil)? Lots of ferrous? Beach/water frequented by swimmers, fishermen, or boaters?
If you have a basic understanding of what each of the search profiles are optimized for by reading the detailed descriptions in the manual and you know your target objectives and the answers to the above questions, you can at least select an "out of the box" search mode starting point simply using the default settings.
Otherwise, post a little more info addressing the above questions and you can get better targeted information.
What I will say is that for fresh water hunting (wet beach or in the water), then don't bother using beach mode since that is designed for salt beach situations and will not be as deep as the other modes. Roughly speaking, if you want to go after high conductors (large silver, clad, copper coins), Park 1. Gold jewelry, nickels, brass and lead, Park 2, Field 2 or Gold mode.
