That's a tough one. I kind of believe your born with it to a point and learn more along the way. I was taking screws off the door hinges as soon as I figured out which way to turn the screwdriver, pulled apart the snow blower when my dad was at work and I was left alone in the garage. It finally got put back together in my teenage yrs when I learn how to assemble engines.
Part of it is how you look at things as a whole or break it down to pieces. It all breaks down into parts or pieces.
It's definitely hard don't get me wrong,it's even harder at least for me is to design something and have it all portioned and laid out correct. Meaning fastener sizes, to spacing, enough material for strength and so on. I don't have cad which would greatly help that design aspect but you still have to come up with it? Try reengineering stuff you can use that's what I tend to do saves you some money "hopefully" and you learn a great deal in the process from how it's made to how to make it.
Part of it is how you look at things as a whole or break it down to pieces. It all breaks down into parts or pieces.
It's definitely hard don't get me wrong,it's even harder at least for me is to design something and have it all portioned and laid out correct. Meaning fastener sizes, to spacing, enough material for strength and so on. I don't have cad which would greatly help that design aspect but you still have to come up with it? Try reengineering stuff you can use that's what I tend to do saves you some money "hopefully" and you learn a great deal in the process from how it's made to how to make it.