[@The1Rolling1Boy] Well, for 2018, Google has transferred SketchUp to a browser-only type of thing. Don't even bother with that. If you want to try SketchUp, go to All Downloads [url=https://www.sketchup.com/download/all](by clicking here)[/url] and get Sketchup Make 2017 (Sketchip Pro costs money). It'll probably come with some supplemental software (Layout and Style Builder). Don't worry about those. If you like having a tidy desktop, just delete them.

Important things to do:
1. Watch tutorials! I recommend starting with [url=https://www.youtube.com/watch?v=YGdLwE4Ue-c]this one.[/url] Though honestly you can derp around in Sketchup as much as you want first. It's a lot of fun to just mess around and see what you can do with it, but you should absolutely watch some tutorials.
2. USE COMPONENTS AND LAYERS. If you learn anything, learn how to use components and layers. Components take parts of your model and isolate them to their own group, which allows you to work independently of them. Layers allow you to hide components. It will save you a low of grief later on, trust me.
3. Have fun. Sketchup is super forgiving once you figure out how all the stuff works. Prepare to lose hours of your life, though.