If you are diving into the document, here are a few core concepts you will encounter:
If you are designing a board that involves soldering discrete wires directly onto the PCB for jumpers or harness integration, is the specific guideline you need. If you are looking for general PCB design rules, you likely need IPC-2221 instead. Ipc-7801 Pdf
(Invoking related search suggestions...) If you are diving into the document, here