Warning: there’s no way the following can live up to the title

Your implementation should be:

• Clear
• Distinct
• Well-Organised

Clear

The implementation should have a clarity of purpose and should express itself in a way which helps the reader understand that purpose.

Distinct

There should be one of everything that’s needed, not a collection of overlapping duplicates.

Well-Organised

A place for everything and everything in its place. Put another way, each level of abstraction should be doing its job.