Leveling up is the way to progress in CastleVille. Almost everything you do earns you XP - this is stored and counted up. When you reach certain totals, you are awarded a new level. Below is a guide to progressing as quickly and efficiently as possible through these levels:
How to Level Up:
The best way to level up is to complete quests. This is designed deliberately to get players involved in the main storyline to CastleVille. Each quest that you complete will earn you the highest amount of points. Otherwise, you receive 1 XP for every action that you perform. Clearly this is vastly inferior to the wealth of XP awarded upon the completion of some of the game's NPC-issued quests. Bearing this in mind, you should save up your Energy and only spend to complete quest objectives - that is from a purely economical Energy for reward perspective.
Your Energy reserves are topped up by 1 point every 5 minutes, to a maximum of 25. With this in mind, you should aim to visit the game every 2 hours, as much as possible. This will mean that your Energy does not reach maximum level where it can no longer recharge for free - thus you will not be wasting any resources. You should also make good use of your neighbors. They can complete a large number of the tasks in your kingdom that ordinarily would require you to use up Energy. Do not waste your own Energy on tasks that your neighbors could potentially perform for you.
Another method for conserving Energy is to make sure you craft the best tools available to you. This will mean for items such as axes to chop wood, you will not have to use as much Energy when clearing woodland, for example. Use the Super Clobber that you can buy in the store with Reputation Points to fight enemies too. It will take considerably less energy to dispatch a Beastie using the Super Clobber than if you try to make do. You also frequently get Energy drops from Beasties, giving you effectively free XP.
You can also buy your way to new levels. Pay to complete quests, advance resource collection and buy Energy to give yourself an extra boost over your friends. Staying on the Energy theme, be sure to use the recipe guide above and cook as many Energy-rich foods as possible. This is a great way to give your kingdom a free boost with the amount of extra tasks you will be able to perform. You can also try pillaging your neighbors. Take their resources of Stone and Wood, and use them to construct your own buildings.