No one yet seems to have mentioned the excellent - free - tutorials provided by Jos P Leh at
http://www.srww.com/google-sketchup.htm.
As perhaps a typical experience, I looked at Sketchup, thought it was wonderful compared with Autocad and other programs I had used before retiring. Then I tried to do more than just create basic shapes, etc., and found it was not quite so easy to learn as I progressed. (Objects didn't do what I wanted, and kept 'sticking' to others, or changing their shapes unexpectedly)
I have approached most other routes to becoming as self-trained computer analyst/programmer/manager using a 'suck it and see' way, with books and lots of trial and error, but this time I just got very frustrated, and cast Sketchup aside.
Some time later, I saw a reference to the tutorials mentioned above, and thought I would give it one last try. The tutorials can be downloaded onto your own PC, so can be run 'offline' and stopped/started/re-run without continued use of the 'net, which was the first good point. (Download them in the background whilst doing something else!)
I took my time and worked through the tutorials starting from the basics, and quickly realised where I had previously made life difficult for myself. As Joe says, 'As soon as a part takes 3D shape make it a component' - and possibly put it on its own layer as well. It takes but a few moments to do so (hardest part is thinking of a name) but the reward is that parts can be manipulated/copied/edited easily - and they do what you expect. Suddenly I 'got' Sketchup, and started to make real progress.
I won't pretend that you don't have to spend some time following the tutorials - and practising on something new (I found with computer programming that you have to set yourself a 'real' task and try to solve it to get anywhere with a new language), but this would be true of Autocad or any other program.
Joe's tutorials are videos of him actually using Sketchup (I found
Jing as a result of this) and he has left in the odd error and necessary correction so you also see how to do things 'wrong' as well as 'right', which is very comforting - especially when you get more experienced and can see that he has pressed the wrong button before he does! He has a pleasant teaching voice and manner, which makes learning quite enjoyable.
I cannot recommend these tutorials enough, they would be worth paying a lot of money for - but then I would probably have never bothered with them if I'd had to pay for them before using them.
If you want to get to better grips with Sketchup, I suggest that you give them a look.
