Defense Maximizing

 A good defensive base means setting up the defensive buildings properly.

  A) Create overlapping defenses.
When you place your defensive buildings, one defense will overlap the firing range of another defensive building, thus creating a area of that will allow 2 or more defenses to target the same area of troops.

   B) Make sure the defenses protect the defensive structures and create a area of damage that  protects the other buildings .
Arrange the defenses so that they protect each other, as well as protect the outside/inside of the base is critical to a well protected base.

When setting up these defenses it's good to know what works best for each Town Hall level.   In earlier TH levels, you won't have the number of defenses to create to many overlapping defenses,  as your base expands you can arrange more so.

 Triangular Defense:

This is a TH8 triangular defense.  courtesy of supercell

 This arrangement, I've found, works best for TH levels 1 -7.  Basically, this means you arrange your defenses in a way that creates a triangle when you draw a line from one like defense to another.   Such as, you have 3 canons, draw a line from canon to canon, these lines should form a triangle.   Now say that triangle points up, take the 3 archer towers and overlap that triangular line from the canons so that the archer towers triangle points down.   Here you've created an overlapping triangular pattern where canons and archer towers are overlapping in their fields of fire, they protect each other as well as protect whats in the center of that triangle, and the spread is good enough that canons protect the archers.

 Ringus Base:

 This is one of the most common base forms, Ringus,  for TH levels 8 and up.  Base growth gives you more defensive buildings and other structures.  This base creates a "ring" of protection around the core of the base.  Core generally holds the TH and or CC, the mortars, and aerial defenses.  Sometimes including the Wizard Towers and storage's.   The storage buildings are placed near the cores, but spaced apart from each other so that they are not easy centrally clustered  targets. They also act as "lures" to attract enemy troops into overlapping defenses to take out the enemy with less loss of resources.   The Ringus base is one of the more well secured and most used base designs, with multiple rings of defense, with an outer ring and an inner ring at the core.   Set up properly it will not be taken at 100% by very many players.

KNOWLEDGE OF DEFENSES

Underestimating the types of defenses in a given base, yours or the enemy in a clan war is a sticking point for the inexperienced.  The most underestimated effect is splash damage upon targeted troops. Two of the most effective defensive buildings are mortars and the wizard towers. These defenses inflict splash damage, meaning their damage goes across a target area. damaging multiple targets at one time instead of single target structures like canons and archer towers. Place your splash damage defenses in places that will allow them to inflict the most damage.  Your mortars  are generally placed securely towards the core of your base, as the mortars are probably your single most destructive defense.  wizard towers are best placed in the inner circle near the storage units, when able.  Providing the storage building is sectioned off in a separate walled off area near the wizard tower.

courtesy of supercell

This is a TH 7 Farming base. archer towers form a square, the wizard towers are in the inner circle, and the canons form second square that overlaps archers...coverage.

courtesy of supercell

The base above is another TH7 Farming base.  The TH is on the outside of the walls, mortars are in the core, and the archers and canons create a ring around the core.

courtesy of supercell

This base is a TH9 Farming base with with TH on the outside of the walls.   The storage collectors are spread out around the outer defensive ring.   The mortars and X-Bows create the inner core of defense.