How to go from theory to practice?

I was recently posed a question:

I’ve seen your post on gamedevse about the entity component system, I had my share of trying to make one by myself, and though your description is beautiful, I fail to see how to code that. Can you give some example on how to go from theory to practice?

There’s an excellent example of an entity component framework with Artemis. Download and study the source code. It may be confusing at first, but stick with it. Artemis really helped me understand how EC systems worked and I’m sure it’ll help you as well.