Imagination

I do not think I need to expand on that one. ;)

Curiosity

Ask questions, lots of them! How do I do this? Can I do this? The more questions you ask, the more you will learn. Administrators generally like new builders who ask a lot of questions. They do not mind answering them. Some administrators enjoy it because it shows that the builder has a genuine interest. Answering the questions makes them look smart, too. ;)

Patience

Patience is actually required in a couple of different ways when you are learning to build.

1. The chances are good that your first area will not be the "Area to End all Areas." Very few people submit an excellent first area. Building is a learning process. If you stick to it, you will master it.
2. The aforementioned administrators who love answering questions can sometimes be quite busy. When your work is at a stand still, wait even if it is hard to. Be patient, they usually get back to you as soon as they can.
3. Building a good area is a long sometime tedious process. Parts of it are not that much fun but are very necessary. If you take the time to do it right, other people will notice the difference.

Common sense, and pride

Use what you disliked in areas to build guidelines for yourself. I.e., I hate when I am walking west in a hallway that assumes I am going east. My personal pet peeve is copied room descriptions; changing one line at the end does not make a difference in my book. There are players who look at everything in the description. Flush everything out with as much detail as you can. Take pride in your work. One new builder told me that most people do not pay attention to such things. I told him I do not build my areas for them, I build them for the people who do true exploration. Just because "most people" ignore the extra work does not mean it should remain undone. A player who only cares about the game will not notice the extra work if it is there; however, a player who notices and explores areas will notice if the extra details are not there. Take pride in your work, be thorough, and you will be a good builder.