Many newbies think that If you have more layers of walls, your village will be more difficult to be destroyed, all enemies’ troops will need to break all those wall to attack your town. When I started play Clash of Clans, I also thought like that. Although it’s not bad, but it can only against Barbarians, Archers and other single-target troops. The enemy can use Wall Breaker to destroy your wall layers easily.
Don’t build your home like this guys!
Surrounding your land with wall
Another common mistake which we can see everyday in Clash of Clans. Many people build a big square wall then stuff all their constructions into it! Attackers can break those wall easily with even just one Wall Breaker, then then can destroy the rest of your town. And if you are not careful, you will omit some space, which can allow the enemies to spawn their troops there.
Within those white lines, attackers can spawn their troops.
Upgrading the Town Hall too fast:
Please stop upgrading your town hall immediately! For some reasons, many players think that this is a good strategy in CoC. But no, it isn’t, you need to upgrade all your defenses first, your town hall is the final step. You can read more about this at: Things you need to do before upgrading your Town Hall