Suntanned skin, well, needs the sun - unfortunately, there are a number of bad things associated with overexposure to the sun.
You need to be aware of those negative effects so you know how to minimize them.
See, when you hang out under a warm light, you're basically a piece of meat under a hotlamp because you're being cooked or baked.
There's a reason that tanning salons are now restricted to ON and up.
Noontime has the most sun, but that's also the best time to damage your skin.
Try not to get your tan during those times.
Sunburned skin can be treated easily with some water.
If you're by a body of water (that isn't salt water), you can dip yourself in until you're comfortable enough to go out.
You can then use one of the many sunburn lotions available to increase your comfort levels.
Your skin needs to be in tip top shape before you put it through its paces.
Try to get as much sleep as you can before you go on any vacation to make sure that it's tough.
You could also cut down on the food and the booze to further strengthen it.
Your diet can also directly impact your skin's health.
Essential fatty acids found in vegetable and fish oils can really do great things for your skin, as well as vegetables and protein.
You could also start moisturizing your skin daily to make it even healthier and more ready for your vacation.
Dehydration is nasty, but you can work around it.
While you're not sunbathing, use a hat and keep things covered up with loose clothing so you don't choke your skin.
Once you're in a diving suit or some such, you can apply suntan lotion to keep things nice and protected.
Just make sure your face is protected as well.
It'd be annoying to get a sunburn just on your face.