Clash-of-clans – Using Gems to Buy More Loot for Upgrades Even Though The Storages are Full

You cant get the king without the dark storage. I just tried and it wouldnt let me spend my gems.

You can't really protect everything, especially if you're leaving for a long while. I don't really think buying shields is worth the gems, myself. Even with a purchased shield, you can't protect yourself for that long.

After it runs out, you're going to get hit at least a couple of times a day, but you can minimize the impact of each hit.

I'd suggest several things:

• Drop trophies ahead of time. Go fight everyone and drop one archer on every base. The lower your trophy level, the less strong opponents will find you, generally speaking. You can always recover later when you return.
• Move your Town Hall outside your base, and put it as close to the center of the map as possible. When someone views your base, they'll start centered on the map. If they can see your Town Hall, the chances are greater that they'll attack you just for trophies. This earns you an instant 12 hr shield.
• Strategically place your collectors. Try to place them in spots where an archer or a barb won't attack them first. Don't group similar collectors together. Leaving your collectors exposed when you leave for a long time increases the odds that someone will do a cheap BARCH-style raid on your base.
• Spend what you can out of your storages. If your storages are deep inside your base, make them as empty as possible so people aren't incented to hit them. You can store a decent amount of elixir and dark elixir in your barracks via overtraining, for instance. Gold can be blown on walls.