I've been investing for about 5 years. Some of this might be helpful, some probably won't because everyone has a different style.
I bank with CIBC and my parents have >100k in assets at that bank so I qualify for what is called loyalty pricing. This allows me to trade for $7 an order instead of $30, I haven't looked into other web services at all so I don't know how that compares, but I do know it's a good price and that's a big deal when you're starting out.
I store my money in a TFSA so I don't get taxed on any profits ever.
I started by picking stocks and following them, just watching the price fluctuate and trying to guess why. My first trade was a year in. It was $1000 and I lost it all. I bought that stock because a family friend told me to, it was never my pick. She lost 200k.
I continued to follow a few companies for a while until I bought $300 of amazon, I made +% on that one (before loyalty pricing so $60 in broker fees, I think I netted -25cents), it was more about building up my confidence. Some time later and ~50 hours of OCD style research into companies I found via sites like motley fool, google finance, yahoo money, seeking alpha, forbes, newspapers, etc. I invested about 15k across 6 companies from 4 sectors, 2 of which were hedged against each other. I bought 1k sirius for shits and giggles recently (I've been watching it since 2007 and wanted a piece). I bought some 1k sony because fuck call of duty and I was drunk (don't do that). I've done well, nothing crazy, but I've made enough to keep me interested.
That's my history, take from it what you will.
My advice, if advice can ever really be given:
Keep your emotions in check. Start with investing a couple hundred dollars and work your way up. You need to build confidence and steady your nerves. I would be able to sleep at night with 40k fumbling along in the markets, would you?
If you can consistently turn 500 into 550 then you're set.
Do not invest in penny stocks*.
Don't put your trust in any one person or source, but listen to them all objectively.
Don't be impulsive. If you are feeling impulsive, do not trade, there will always be another opportunity.
If you insist on short term trading, wait until you've got some experience and success with long term trades. Short term is way more emotional.
Don't buy a company if you don't understand their business model.
1 company = 10+ hours of research.
If you have don't your research and are still unsure but want a piece, hedge it with a polar company in the same sector (eg. gold goes up when the dollar goes down, buy both).