This is a thread in which you say you're going to model something, which is a WIP thread. A WIP thread requires pictures of your progress, not a render of what you say you're going to do. It's not complicating it, it is making it follow the rules.
To take a Windows screenshot, just have your program (Sketchup) open, position the model how you'd like it to be seen, and then hit the Print Screen/ SysRq key on your keyboard. It's in the upper right hand cluster, usually with Scroll Lock and Pause/ Break.
Then open an image editing program (Photoshop, MS Paint, or GIMP, the last two of which are free) and Ctrl-V into a new image. Save the image. Voila, a screenshot of your model's progress.