My hubby and I started taking our son beach camping at 7 months. We have an RV, so that makes it easier, since he has always had his own room. We did tent camp once, though, and we have a huge tent that he slept in with his pack and play.
My advice, just have fun. We didn't worry about keeping everything clean and organized until it was time to leave.
We also planned our meals ahead, and made them all very simple. Rather than eggs and bacon and stuff for breakfast we did muffins or croissants, sliced ham, milk and juice and coffee. For lunch we just had snack foods like chips and 7 layer bean dip (can be made healthy)or an occasional sandwich. For dinner we did everything outside with paper plates, like burgers or hot dogs, and had dry sides like chopped veggies or chips.
We would give him his bath at night and put him to sleep in his pack and play in the rv, and then make sure we didn't need to go in there until bedtime (get everything you need for the evening ready before you go to bed. I would bathe the baby and my hubby would "pack" for the night). That helped him to not get disrupted.
Another thing that we couldn't live without was a fan for the tent, so he wouldn't get too hot during naps, etc. My hubby and his friends would go down to the beach during nap time, and my girlfriends and I would lay out at our campsite until the baby woke up. Then we would go to the beach. He was able to sleep without any issue. Or you can always take the baby for a walk in the stroller, and they can nap there. But again, the schedule might get a little haywire, because there is so much new to see and do. If your baby can't take a good nap, just make the bedtime ritual a little longer or put her to bed earlier.
If you are tent camping, bathing will be much easier if you have one of those plastic bath tubs for the baby. Also, go to the dollar store, because they have cool plastic bath caddies for $1. You can get them dirty and just rinse them off. Will also help you keep everything together, because you can put it all back in wet or dry.
Take a large beach blanket (or a couple) that you can use down on the beach, as well as at your campsite. This will give the baby space to walk around without getting too dirty.
Sun umbrella! Give your baby some shade. And LOTS of sunblock. We use Neutrogena. Works great.
Don't take your diaper bag to the beach, get a cheap beach bag at Big Lots or Walmart, then put just the basics of what you neeed to take to the beach. We would put 2 diapers, a swim diaper, sunblock, towels, bottle water and formula (in a cool container), wipes, and snacks. It limits what you need to lug around.
Hmmm... I know that's alot, but it will help. Basically take the bare minimum of what you need. Pack the bare minimum of what you need. I usually take swim shorts for my son, 1 other pair of shorts, 3 shirts and 1 jammie.
It's definitely more stuff with a baby, but it's not really all that difficult, and should be really fun! We will be in San Clemente all August, so if you need supplies, you can always pop over to our site!! =)
Have fun!