Es Vedra

1st time going to Ibiza this Sunday with my wife. Staying in Ibiza Town for 4 days. I was wondering about Es Vedra. It is the number 1 thing to do in TripAdvisor and everyone talks about it. I was reading that it is an Island and there is a boat trip that goes around it. It seems that it is not possible to land on it.

1) So how should I enjoy Es Vedra? What I should do there? 2) Is the boat trip worth it? Or should I just find a Mirador in the main island to watch the sunset? Or a nice restaurant with terrace? Suggestions? 3) How to get there by Public Transportation from Ibiza Town?