Builders are players with Build privileges in the Creative world. You do not need to donate to become a builder, just prove that you can Build aesthetically pleasing structures in our other Worlds. The decision about whether to promote a user to Builder will be taken by the Moderator team.
Include pictures of your structure as well as it's co-ordinates (you may find the co-ordinates by pressing F3 in-game and noting down the X, Y and Z values). You can take pictures of your building by pressing F2 in-game, the screenshots are located in the /appdata/.minecraft/screenshots folder. You may post your screenshot in your post using the 'Upload a File' feature of the forums or by uploading them to an imaging hosting site such as imgur. Take your pictures in daylight! APPLICATION MUST HAVE 3-5 PHOTOS!
The moderators will discuss your application and decide whether to grant you builder status.
If accepted you will be upgraded in-game by a Moderator or Admin. Your thread will be moved to the 'Resolved Applications' section shortly after.
If You Get Declined
It does not mean you will never be able to play on Creative! You just need to practice your building skills. Try copying something in real life to the best of your ability. If it goes wrong, try again.