its brand new right? Im sure they told you about the break in process right? and dont forget to take it in for service first time, it helps keep your warranty. just hold on and have fun.
there are rules on water so make sure to know them. keep an eye for other boats and watercrafts.
watch for debris in water, tree branches and sea grass.
sitting down on choppy water will make your bum hurt, stand up if you can but watch your back might hurt after a while.
make sure you got all the equipment in before going out (docking line, fire ext., whistle and life jackets)
allways keep yor lineyard hooked to your wrist or the jacket.
take it easy first time, do some slow turns to see how it reacts.
remember if there is no throttle, it will not turn.
there is no brakes on the boat or ski, so be carefull.
ask questions if you dont understand anything, its good to know it before you do something wrong.
good luck!