Quoting AaronLP, reply 18How do you guys actually start the modelling of spacecraft/structures do you just go and play around till u get a look you like or do you have actually blueprints/plans so to speak, if not any of those 2 do you just go from concept art too give you a reference point?
I started by making a cube, then making a slightly more complicated cube, then I made something unbelievably deformed and just kinda improved from there.
If you want to get decent, expect six months of training before you can competently do most of the basic techniques. Expect to do this for at least a year before you can try more complicated stuff without spending two days on a two hour job.
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good to know 
Btw, concept art is great if you know what you are doing, and most of the 3D packages have some sort of rotoscope option so you can overlay the concepts in your viewports and work directly over them.
For absolute beginners, I recommend just playing with the software and/or freestyling, at least until you get a solid feel for the interface and tools.
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ok will do.