A foreshortened compound shape is difficult! However, within the larger box that the astronaut is sitting in, everything should be aligned to THAT huge box as well. So it's good to think about the angles of parallel things all aligning, such as the collarbone, to the waist, etc.
By Trevor Snowden
For how to do this with objects that aren't as boxy:
Aligning Rounded Compound Shapes
For this specifically with cars:
Don't just take my word for it. Here's Kim Jung Gi explaining it:
