Tutorial Making Buildings for CitiesXL using Sketchup v1.00

Migrator's note: aitortilla01 is the original author of this tutorial.

Do you find that most of your dream buildings are already in the Google 3D Warehouse? Do you find it easier to model in Google Sketchup?
Learn how to bring (almost) any building from the 3D Warehouse collection to Cities XL! This tutorial will explain carefully and with tons of images all the necessary steps to do so: how to improve your models in Sketchup and make them game friendly, the software and tools you need, how to export your model to 3DS Max, how apply textures to your models and finally how to export them to the game!
Every step of the process is covered in this tutorial!
As an example, I use the John Hancock Center that I released recently here.
You will see how to go from this...

to this!

Acknowledgements
This tutorial has only been possible thanks to the many experienced users who have been patient with me and helped through the many problems I found.
Disclaimer
This tutorial is simple and should help you get the job done, but it will not explain how to do modelling with Sketchup (for that there are tons of tutorials on YouTube).
It does not get into exhaustive detail. You will learn how to model and bring to the game basic buildings; only experience and practice, and asking for advice in this community will help you get better.
Please do not flood me with PM if you have questions! open a thread in the corresponding forum where anyone can help and share their advice.