I have had a g-cat 5.7 for 20 years.

Step the mast and set the boat up completely while it is on the trailer. This includes placing the sails on the boat, and preparing them to be raised.

Release all tie downs on the trailer except the bow tie down. Carefully back down the ramp (avoid other vehicles and boats until you get good at this). By the time the wheels of your trailer are wet you are ready to launch the boat. G-cats draw very little water and have no centerboards to worry about.

I suggest you wear water shoes or teva sandles, the ramp may have rocks or borken asphalt.

Be sure you have a long bow line and a longer stern line. Have your crew hold both. Release the bow tie down. Push the boat off the trailer. It will float. With 2 lines you and your crew can stabilize the boat bow into the wind (or if there is a dock, walk it to the dock).

By this point you should be wet to the knees or maybe more, but if you actually go sailing you will be getting considerably wetter! Place a towel on the front seat of your vehicle. Park the vehicle.

Return to the boat and with your crew raise the sails. Jib first (leave the sheets loose), you can use a bungee cord to wrap it up around the forestay while you raise the main, this will keep the boat from sailing away before you are ready. Raise the main, again leave sheets loose and keep the bow into te wind as best as you can.

Take your positions. If at a dock push off. If afloat, back the jib until the bow comes around. Sheet in and go for it!!!

Dock tips. It helpd to point the boat out towards the water(eg, turn it around from the way it came off the trailer) before you raise your sails. I keep a couple of small fenders for when I tie up, but your throwable pfd will work as well, otherwist you can get some fiberglass dammage from 'interacting' with the dock.

Don't be afraid to ask for help, and, remember you are going to screw this up!! For the first year I had my cat, a successful sail was defined as no hull dammage or permanent injuries!