There is no such thing as building something yourself. When you make something, you use tools, materials and methods made by other people.
The most important part of building something that isn't crap is being able to recognize the crap in what you are considering for use. Then deciding if you can contain the crap, or find a less crappy alternative.
The most important part of building something that isn't crap is being able to recognize the crap in what you are considering for use. Then deciding if you can contain the crap, or find a less crappy alternative.