How to reach? The only way to reach would be to Hire a Long Traditional Boat that adds up to the charm of the day or to book a Day tour package from any of the many available. Remember, The part of the Beach is actually a National Marine Reserve Park and you do have a Ticket to this beach, it cost THB400(Rs.800). So while you book package, make sure you need whats Included and Whats not? You may leave a package for 100-200 THB but you will have to shed 400 at the entrance of it. Do not get tricked by many of the tour operators who promise the day tour package at the lowest price like 1300-1400THB but you end up paying more for the National Park entry fee separately.
I personally suggest Patong Tours (AndaVaree Operator) which provides a day tour with free pickup from your hotel in Patong or Karn point at an all inclusive price of THB 1600/- . Had a good times with them, while booking i did not know that Patongtour.com website would actually get me to Anda Varee. Nevermind, I felt the tour was good enough to give them a 4-star. If you say, you had to see a houseful crowd on the Phi-Phi or Maya bay island then that's not the mistake of the operator, it's how touristy these island have become lately. A special mention to Jenny and Rudy, our tour Guide for being the best possible, humorous and fun loving people i met in Thailand