Get there early. And by early, I'd recommend at or before park opening time.
On the weekends, the place has generally been done admitting guests by 11am to noon, sometimes earlier if there's a holiday. Later if the weather is poor (rainy, cold, etc).
Plus, if you don't get there at around opening time... you're going to have a lot of trouble finding an open beach chair.. much less several grouped together!
It's an awesome park, but until the new-park fervor calms somewhat... plan on making it in there super early! Or, at the very least, call ahead of time to make sure they're still admitting guests before setting out for the park!
=)
