Beauty: As far as beauty goes, it is what it is by definition. Beauty is also very controversial and has a past that has a great history. Yet, with this history, it has not changed much since human eyes can only handle certain shapes and sizes, color, design, sound etc., in accordance with harmony and balance.
When doing art I think all people should use several different philosophies or guidelines to reflect on for inspiration. Here are a few interesting subjects to look up for beauty tips:
Phi- The key to body proportion.
Macrobiotics
Wabi Sabi
Aesthetics
Romanticism
English Art
Waterhouse paintings
Egyptian & Greek/Roman art
Style dot com
Go to your local library, bookstore or museum.