Try to find a trustworthy dealer with a good selection of equipment. Audition lots of combinations.
Read lots of reviews, etc. not so much to pick the merchandise but just to learn the jargon and get a feel for what you are looking for
Make your biggest bet on speakers
within reason, if you can't afford what you want, wait until you can. Otherwise, you run the risk of buying something that is unsatisfying from day one
don't make lateral moves. If you're upgrading, plan on spending twice what the old component cost.
there are components that offer Great value but realize that you generally get what you pay for just like in anything else. There may be components that sound better than others that cost three times as much, but I would suggest that is generally a unicorn.
you can learn a lot from a forum such as this, I certainly have, but take the know it alls with a grain of salt. Hearing is subjective. If it sounds good to you, that means it's good.
most of all, enjoy the music. Spend more time, listening to music than reading reviews
and never start a thread about the merits of high dollar switches