To pick up a mooring, start your engine on your approach (if it's not already running) so that you can begin to douse/secure all sail well before you get about 100 yds. from the fairway mouth, and when once there, hail Avalon on VHF channel 12 ("Avalon, this is the [boat name]" "Avalon, we are a _____-ft. sailboat requesting a mooring for [length of stay]." The Harbor motor launch will meet you there (often they will come to greet you before you can hail the harbor master; if there are boats waiting ahead of you, just be patient, and the motor launch will come to you).
A technique I've found convenient at this point is (with all sail down, of course) to shift into neutral and let the yacht come to a stop, then shift into reverse, and let the bow blow down directly downwind. Depending on the strength of the breeze, you'll pretty much be keeping station in one spot while interacting with the harbor launch.
Picking up the mooring can be tricky for the uninitiated. You will be assigned your mooring by the launch; it will be numbered like a stadium seat: a row letter followed by a number. A is the row closest to the beach. Tell the launch operator you're a first-timer and ask him to point it out for you.
Print out the mooring diagram & directions on the visitcatalinaisland site, and make sure you study/discuss the mooring procedure with your crewmen ahead of time as you cross the channel.
After you move down the row and spot your mooring, take note of the wind direction and how much room you have . After you swing around for your second approach, close on the buoy from directly downwind, aiming for the pole. Come in slower than your instinct tells you: unless there's a breeze up, the slower the better, because the tendency is to over-shoot.
The diagram and directions given on the site are good, so I'll just give a couple of tips about securing your boat to the mooring:
Your crewman's job is to pick up the mooring buoy by the pole, haul it aboard, find the bow hawser (the big yellow loop) and secure it to your bow cleat (pass it under the lifelines!), then run the thin sand line to the stern cleat. As the diagram shows, the stern hawser is at the end of the sand line.
The best way to walk the sand line to the stern is to remember to haul the line energetically and to walk to the stern at the same time. Your line-handler has no leverage to keep the stern of the boat from blowing down if he's still standing at the bows. Get to the stern quickly.
You may find that simply throwing the stern hawser over the cleat doesn't offer a snug berth for your size boat, and that it's better to haul up some of the hawser and cleat it off.
Getting to shore can be accomplished either by your own small craft or by hailing the shore boat to come to you (a couple of bucks each way per person). There is a whole etiquette involving dinghy tie-up at the dinghy pier that you will get to know, but the basic rule is that you tie off with plenty of slack to allow others to push you aside so they can nose in and tie up. If the pier is packed, walking through others' dinghies while arriving or leaving is customary.
Just about everything else you need to know is on the visitcatalinaisland.com site.
Have a great trip.
Jeff