Once you've identified all your entities, establish a clear guideline for their relationships. This can be done via presentations, flowcharts or even reports.

2. Create a functional specification and project plan

This part, in my opinion, is the most important part of the project. Functional specifications (or functional specs) are a map, or blueprint for how you want a particular Web application to look and work. The spec details what the finished product will do, user interaction, and its look and feel.

An advantage of writing a functional spec is that it streamlines the development process. It takes discrepancies and guesswork out of the programming process, because the level of detail that goes into the plan makes it possible to minimize the misunderstanding that's usually associated with project mishaps. See examples of well written functional specs at RayComm.com.

Once the functional spec is finished, a project plan must be devised. A project plan is a timeline of tasks and events that will take place during the project. The project or program manager is normally the person who creates a project plan, and their primary focus is to detail task notes while being able to accommodate scheduling and resource information. You can download a sample Excel file for a project plan at Method123.com.

3. Bring the application model into play

As discussed earlier, the application model consists of 3 tiers - The User, Business and Data service tiers, each of which serves a substantial purpose.

Practically speaking, it's always best to start with the data tier, because you've already identified your entities and understand their relationships. The data tier can be an SQL server database, a text file, or even the powerful and robust Oracle. Create tables, relationships, jobs, and procedures depending on what platform you have chosen. If the data is a warehouse (i.e. the data already exists and does not depend on real time interaction), then make sure that new and additional data can be added securely and in a scalable fashion.

A quick tip: using views in SQL server/Oracle can improve dramatically the productivity and performance of your application. They increase speed because they are "stored queries" that don't have a physical existence.

The Business services tier, in my opinion, is the heart of the application. It involves the implementation of business logic into the scripting or programming language.

At this stage, make sure you've already set up your environment for testing and debugging. Always test on at least 2 instances in your application, after all, what may work perfectly for you, may not do so well on other platforms or machines. ASP, XML, PHP, JSP and CGI are some examples of server side scripting languages used at the business service level. Whichever language you choose, make sure that it's capable of handling all the business logic presented in the functional specification.