I did the best I could to get the best parts for the lowest price. My budget was around 800-900 USD, so I researched parts, set them on watch lists, and waited to see which ones went on sale. I looked up other part lists, to see what parts were common and well reviewed, and eventually worked my way to a pretty substantial computer for not too expensive.
Some stuff I already had when I purchased the PC, (the keyboard, mouse and monitor) but they are certainly part of my setup.