So, TH7 is one of the biggest jumps in CoC. Dark Elixir, Heroes, 175 walls, your final Mortar, and the last army camp. It's kind of a big deal. This is when raiding becomes massively important. Upgrades are now 400k minimum, and go all the way up to 2.25 million. So, resources are at a premium. If there is any base I would recommend farming at, it's this one. On my profile, I've created a load of Farming bases, ranging from TH5 to TH10, though I've focused on TH7. (I'll link my profile at the end, and I'll be linking to certain bases as examples through out this guide. So, onto the basics
NUMBER FREAKING 1) PUT YOU BLOODY WIZARD TOWERS NEXT TO YOU STORAGES!! If you aren't very astute, this is pretty important. Wizard towers are one of two defenses in tha game that do splash damage, which allows them mow down hordes of tier 1 troops. In a perfect world, you could get each Wizard Tower to cover one of each storage, and your DE storage. See here: http://clashofclansbuilder.com/plan/536304 )That's pretty much my best example of How your wizard towers should be placed. Each covers 2 storages, and the DE storage. Also, your Wiz Towers should be behind 2 layers of walls, much like your storages and mortars.
2) Place the storages behind at least two layers of walls. This prevents a mass swarm of archers from just shooting over your first layer of walls and taking all your hard earned resources. This also means that ground troops are going to have to melt through two layers of walls, giving the rest of your defenses time to take out the attackers.
3) Wall staggering. It's absolutely necessary in CHAMPS, but it's incredibly useful at this level when the armies are much less expansive and you're forced to really budget you troops.
4) Well, this is the obvious one, but put your TH outside the walls people. You're only going for resources, so defense doesn't matter. Anyways, if you're worried about trophies, A BARCHER farming army can easily get you 50% if you make sure you clear out all the outside buildings.
5) Protect your DE. It's pretty damn important, even though our abusive step father (Love you SuperCell) of a developer doesn't give us a drill at TH7, you can get planty of DE just by raiding inactive TH8 and TH9 bases. I'm currently a TH7, and I have level 2 King, and level 2 minions and hogs. (I'm about 6k from Level 3 king btw.) However, if you're sitting on your hands because all your builders are busy and have crazy amounts of elixir because you're a raiding god ;) Whip up an army of dragons, and bum rush an unsuspecting TH8 or 9 that has neglected their Air defense. It's pretty espensive, but is highly effective every once in a while.
6) Hide your Clan Castle. This is applicable for any plan at any level, but still, do it.
7) Don't break the bank on your armies. I actually use 100 Barbs and 100 Archers, and drop the king when necessary to pick up some hidden DE. Giant Healer isn't what you want to be rolling down the street with. Get a new clique, the cheaper the better.
8) I'm really bad at planning, pretend this was number two. Be picky about what base you raid. Personally, I don't attack unless there's more than 200k of each reasource, and I prefer for most of it to be in the pumps. BARCHER isn't going to push through to the core of the base, it's good for MAYBE one layer. so, don't attack bases like the one I linked earlier, as you'll belucky to even get inside the base. So, make sure there's 400k combined, and try to make sure it's all in the collectors.
9) Ignore Females, Acquire currency, multiply SWAG
That's all. Here's the link to my profile, that has a bunch of farming base designs