Defining the track layout is a crucial step. The risk at this stage is analysis paralysis: the project never gets finished because you're unable to decide. This difficulty stems from the awareness that once a choice is made, there's no going back. It's a bit like freezing a dream, which by its very nature is undefined, into a concrete example that you want to represent it. It helped me to design six different computer-generated variants for the space defined in step 2. Thus, having explored the pros and cons of the various solutions with respect to the desired functionality, I gained the necessary confidence in the choice made before even laying a single physical track.

For this reason, software such as Wintrack (Windows) or Railmodeler (Mac) are a fundamental—I would dare say mandatory—tool for defining the layout of a three-dimensional (multiple levels) model. I know many are tempted to rush ahead and experiment with physical tracks directly, but I can assure you that the software provides unparalleled forecasting capabilities while also offering the ability to visualize and experiment with the final result.

Using Wintrack software (as of 2021, I used version 15), you can precisely define the track, checking in real time whether it fits within the available space. It's also possible to view the result in 3D from multiple angles, as well as simulate being on a train traveling on the layout. The biggest challenges are learning to use levels and how to set slopes on uneven sections. The software also highlights the heights in areas where the lines intersect, indicating critical areas if they aren't sufficient.

Below is the 3D view of the latest version of the project I created for Massa sul Cesi.