Read first--it will actually help you figure out your goals. Harley's book may be the bible of high end audio but another very useful book on basics is Jim Smith's "Get Better Sound"--i found it helped me focus on the room as being the most important part of an audio system as many have mentioned here (unless of course you're focused on headphone listening only. He isn't solely focused on the room--many other useful principles are discussed in easy to understand terms and style.
Question: What are some of your best pieces of advise to someone new to the hobby?
I have a friend who is interested in putting together a system and am putting together a little guide for him, compiling information I’ve found over the years, plus some of my own personal tips and tricks. However, I am by no means the end-all-be-all of knowledge and want to incorporate information, tips, and tricks from the community - however basic they may seem - into a nice reference resource.
Without specifically naming any pieces of gear or brands (this isn’t a product recommendation question), what are some of the biggest tips, tricks, important pieces of info to keep in mind, caveats, etc. that you would have for someone new?
*side note - hopefully this post can also serve as a nice reference point for people in the future, as well!