Drop a barbarian or archer to test for clan castle troops and/or traps outside the walls. If there are clan castle troops take them out with the lightning spell or if the troop is a Dragon, then drop you own dragon and 3-4 wizards, spread out.
If there are no Clan Castle troops, then drop the Lightning spell on either the highest levelled Mortar or highest levelled Wizard Tower.
Send in all your Giants at one wall, and drop your first healing spell.
Send in 3 wall breakers to breach the first couple of layers of wall.
Now send in your Wizards, Barbarians and Archers from the same side. Having a Barbarian King will also be useful.
Wait until the nearest/highest level Air defense has been taken out for you to send in your Dragon.