What??
JUST. SHUT. UP. YOU. FOOL!!!!
a_person - just ignore the above post - the guy is talking out of his arse!!
When you first get to the water, take your time and work out the time period between the sets - get a feeling for how the waves are breaking, etc.
Then look for any channels or rips that'll help you (clue - look for flat areas between the peaks)
Now - as Danny Boy says - walk out as far as you can (as long as that doesn't leave you in the impact area) and wait for one of those lulls - then go for it!!
If you HAVE to turtle roll, then paddle towards the wave at 90 degrees and then when it's about a couple of board lengths away, roll over, holding the rails at the point you'd normally place your hands for a pop up.
Keep some downward pressure on the nose end and allow your legs to fall toward the seabed - so you end up sort of doing an inverted handstand on the board (it won't quite get that far, but it gives you an idea).
Doing this will end up like an anchor to minimise any movement back to shore - you need to give yourself plenty of time to 'sink' and keep a good hold of the board, so make any move quite early.
Once the wave has passed, pull up and flatten your body back against the board as you roll it back upright - not always easy, but all about practice.
If you don't make much progress and end up further back, then that's just down to lack of paddle strength and timing in the roll.
Have about 15 minutes of full on effort to get out back - but if you're still not getting past the impact zone, go back into the shore and take a breather - when you've recovered, try again!
Hope that helps a bit............
