I keep it simple - just a herring under a float. In the old days, my uncle used a rubber ball for a float and cast it out. About 10 feet under. The largest was a 45 lb buck off of the jetty. It was an epic battle landing it. These were the old days and I believe you cannot use a gaff for salmon today. I am not sure I could use a net very well off of the jetty.
I have never seen the bobber go down as I usually am reading a book. Then I hear the drag going and it brings me back to reality.
Good luck!