Here's how I go about it:
- What's my stored data?
Design the structure of the data for the application
and classes that will access the data, starting with the
tests that verify that they are doing the right things.
- How will I display my data?
Write classes that will call the data and filter it out into a display.
At first write some dummy data to play with.
(These days I write pseudo data tables with
the classes so that I can call them easily for testing. DBD::CSV is a fav.)
- How will I write my data?
Write forms that will send the data via its classes to the database.
- How will it look?
Create templates that the data can be punched into.
These steps can be very simple or very complex, depending.