I get an annoying amount of email from people asking me how to gamble like I used to. The truth is that what I used to do isn't profitable anymore. It was a right time, right place sort of scenario. Although I'm not a professional gambler anymore, I have been spending time studying and improving at poker (I'm a break-even or slightly profitable player), and I have friends who are pros. There are surely several different paths you can take to make a living gambling; this is the one that I'm aware of and is feasible for someone of above average intelligence.
Despite offering a rough guide to making money gambling, I don't necessarily recommend that you do so. I gambled professionally for seven years. During that time I made a lot of money and enjoyed my life. One morning I woke up and all of my money was gone. The story behind that is complicated, but the gist is that "they caught on". The strongest emotion I felt was a sense of relief. Gambling is fun, but it's not "big". It doesn't contribute in a meaningful way or leave you with a body of work.
Most casino games have a house advantage ranging from 2-5%, assuming "perfect play". That means that if you play perfectly, you can expect to lose, on average, about 2-5% of the action you put through a machine. Perfect play for slot machines is simply to bet the maximum amount of coins (the jackpot is skewed heavily in favor of maximum coins). For blackjack you need to memorize what to do for every combination of player hands vs. dealer hands, specific to each set of rules (hit on soft 17, resplitting aces, etc).
Because this is how casino games work, you cannot expect to win long term at any game with a house advantage. It's not possible unless you have some specific edge that counterbalances the house advantage, like counting cards. So if some one is a "good blackjack player", that --- at best-can mean that he only loses 2% of his action on average.
Poker is different, which opens an opportunity for professional play..
In poker you play against other people, and, as an extension, your potential profits come from other players. The casino cares if you take their money, but couldn't care less if players take each others' money. They collect their profits in poker through what is called a "rake", which is a percentage of every pot. The rake is usually around $4 per hand for small or medium limit games. If it weren't for the rake, you could be better than just 50% of the table and expect to make money. With the rake you need to be better than 80-90% or so (a rough guess). That's why you have to be GOOD at poker to win at a casino.
The good news is that being that good isn't very difficult in the lower limit games. Most poker players in these games are absolutely atrocious. As a new, but properly training, player, you'll be far better than most players at the table. Not enough to win right off the bat, but good enough to leak out your money slowly. Think of it as paying for an education.
You should have a few thousand dollars that you can afford to lose if you're going to learn to play poker. You may never dip down below $500, or you may get down to $1990 and only then start become a winning player. It depends on you just as much as it depends on chance.
I play limit poker. That's mostly a function of having started playing it before I started playing no-limit. The game is easier to become proficient at, can provide a healthy income (count on between 1 and 2 big bets per hour, so in a $3-6 game you might make between $6 and $12 dollars), and is harder to go bananas in and lose your whole bankroll in a day.
Never play super low limit poker. It's not effective for education because the players are so loose that it doesn't really reflect a normal game. It's also not effective for making (or losing slowly) money. The rake is often $4, which is two big bets - enough to make it virtually impossible for even an excellent player to make money. Start at $3-6 and consider going up to $4-8 or $6-12 when you get more comfortable. In $6-12, that same $4 rake is only a third of a big bet. That's 1/6th, proportionally, which makes a huge difference.
I don't have enough online experience to say much about it, other than to tell you that I avoid it. It's a very different game because people are playing multiple tables and using statistics overlays to help guide their decisions. It also feels a lot like work. I suggest playing in real life if it's possible, but I'm sure others would disagree.
The basis of a winning game of low limit hold'em is tight and aggressive play. That means that you tend to play a much smaller pool of hands than your opponents, and then really take control and go after them when you do play. Most players are the opposite - loose and passive. Some are loos and aggressive. Almost no one is tight aggressive.
The first two books you should read, in this order (prescribed to me by professionals), are :
1. Winning Low Limit Hold'Em by Lee Jones. This is basic enough that a beginner can pick it up, but has enough solid strategy to build that same beginner into a break-even or slightly positive player (in other words-it got me where I am). Take the time to memorize the starting hands. Once you're a bit better you can veer from the recommendations, but as a beginner it's very nice to have one aspect of the game completely out of your mind. (If you're into pickup, it's like having a few openers memorized.)
2. Small Stakes Hold'Em by Sklansky and Malmuth. This book just ripped apart my brain, rewired it, and jammed it back into my skull. If Winning Low Limit Hold'Em will convince you to be tight, this book will teach you to be aggressive. It focuses on a lot of the math behind poker, and some more advanced plays. My poker pro friend who recommended this book told me that by understanding all of the concepts in it, you should be able to beat any game up to 15-30. That's $30-60 per hour.
I've found it immensely helpful to have friends who are also excited about learning poker. Even though they're all newer to the game than I am, I benefit just as much as they do because we now constantly talk about poker concepts and hands. Having a peer group learning with you really helps create an environment conducive to critically thinking about poker.
The last part of the formula, which comes as a surprise to no one, is practice. You need to have a lot of hours of poker experience to create bones for the meat of your learning to attach to. When I first read Winning Low Limit Hold'Em, a lot of it flew right over my head. But after playing a lot, I could think of specific situations I had been in which fit the examples of the book. That helped concepts stick. My favorite routine is to play at the Bellagio in Vegas for a few hours, go sit by the pool next door at the Cosmopolitan and read for an hour or two, and then go back to the tables. Besides our now-monthly trips to Vegas, my friends go to a local card room nearly every single night and play for a couple hours.
Track your play on your phone. Poker Session Logger is my choice for Android, and Poker Journal is the one to get for iPhone.
Even if, like me, you don't want to become a professional, poker is a really great thing to learn. For one, it teaches excellent risk management, critical thinking, and decision making. A lot of the skills are the same as the ones I've learned-and benefited from-through my earlier gambling. It's also a nice backup to have. Play well enough and you know that if you ever have no source of income, you can go play poker. It opens up the possibility of free trips. Even as a much worse player than I am now, I was able to easily recover 50% of the cost of sailing on the Queen Mary 2 just by playing poker against my fellow cruisers. Vegas is such a cheap place to fly to and stay at, that I imagine my trip in March may be the last that costs me money (in expected value, of course. a weekend isn't long enough to remove variance).
A couple more quick tips: Tip the dealer $1 per hand that you win. Don't get carried away like some players and tip him large amounts. That cuts into your earnings. Don't show your hand or tell people what you had unless it's your friends (who can give you feedback and talk about the hand with you). In general - don't look for anyone else at the table to serve as a role model. Most people you see with large stacks of chips have gotten very lucky short-term and are probably way down overall.
If you live in the San Francisco area, you can play at Oaks Card Room in Oakland. It's awesome. I'm there every night.
It's crunch time, so don't expect more than a post a week for a while. I'm working on my programming project AND a speech for SXSW. Lots to do!