As a collector / dealer, who originally got into comics for the sheer love of it, I would recommend a few of the following:
(1) Collecting comics is very much like collecting art, you must have an eye for it - be aware of potentially hot artists, buy popular artists work before they die and sell it quickly afterwards.
(2) It's much easier collecting with a partner to reign in those expensive, honestly...it will make money, purchases. If you must buy it though, you better make damn sure it makes a profit
(3) Don't start collecting after you get married - they just think you're spending money for the sake of it!
& why..oh why are you on the computer again / at that convention this weekend / on the phone again - it wasn't like this when we first got married,
(4) Personal Enjoyment / Legacy - Collect to please youself and to leave your loved ones something. I started off with very little and ended up with enough to keep my family in clothes and have a personal collection that will be passed on to my sons (If they're lucky)
(5) Ignore mates / friends / extended family members who think you are a 'Geek', illustrate to them 'Comic Art Potential'. It worked for me - Now there are very few dissenters, and plenty who want to buy shares! ( Or be a director of external sales or something!!)
(6) For the love of God enjoy yourself & disregard all the rest, strive to be the best and achieve those goals you thought were out of reach.