Hi,
Character Builds are placed in the character build group. You create a build by making a forum discussion within that group (use the 'add' button on any page within that group - the same method you used to create this forum discussion). Character builds follow certain basic guidelines (for example all character build titles use the format "Character Build: Name of Build". These guidelines can be found in the group information page. If you have any specific questions regarding character building, you may ask those on the the character building help desk page.
Good Luck