If you are looking for PHP coding standard, the one published by Zend Framework seems reasonable to adopt. Following a coding standard and documentation is as essential as the code itself. Haphazard code with no style creates a messy code which can be very difficult to maintain. Even if you are the only coder on a project, after a few months you’ll be stuck with your own code and avoid editing it.
Properly formatted code is easy to read and follow. It is important to remember that code is not only for computers but for humans as well. We have to maintain the code by adding new features or fixing old bugs. Even if you have little documentation, a properly formatted code will take less time for another developer to read and follow. This is where coding standards help. By following a published standard other users can follow your code easily.