Phuket to Koh Samui

Me and a friend are going to Full Moon party in Koh Samui . We will be travelling from Phuket. We have seen there is a flight from Phuket with Bangkok airlines to Samui airport i think, but we were wondering if there were any other ways to get to Koh Samui from Phuket.

Thanks :)

Taxi, bus, minibus, walk.
And the 'full moon party' is on Koh Phangan!

the bus is straightforward, and a lot cheaper than a flight.

Scroll abt 85% down this page http://phuketdir.com/phuketinfo/helpful.htm#boatschedules for buses out of Phuket to Samui and to Surathani for Phangan ferries.
Note any guesthouse, hotel, small or big travel agent will be able to sell you a minibus/ferry ticket right onto Phangan or Samui - less comfortable but has the advantage of usually picking you up from you beach accommodation v getting into Phuket town for the buses.

The bus station in Phuket Town can sell you a combo ticket direct to the island.