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He may be young, but he knows Sketchup. Some of it may be simplistic, but hey, if you don't know Sketchup, then simplistic is the way to go. He has multiple videos that explain all of the commands, options, etc. Layers is actually not that hard. First, draw a part, then triple click on it to select the object, then right click and select Make Group. Next, select the object if it is not highlighted, then click on Window ( in the Menu bar at the top), then select Layers. Click on the + button in the pop up window. This adds a new layer (Layer 01, Layer 02, etc.). Under the Entity Info box, click on the Layer box, then select Layer 01. You have now added your first layer. If you wish, you can rename the layer to something of your choice. If you do this, then the next time you add a layer, then Layer 01 will again be added. This is the default setting.
Whichever way you go, start on the first video and progress from there. You will quickly pick up on Sketchup.
Happy drawing.