I do play progressions; but I also understand the math behind the arguement that the progression doesn't change the house advantage. Based on my own experience, however, I can't play as long nor have even a decent chance of walking away ahead if I simply flat bet. But keep in mind that progressions, especially negative ones (where you increase your bet as you lose) can carry a big risk. You can win like crazy for a good while, and then crash really fast.
The basic idea of the negative progression is to re-coup your loses with each win. So, for example, if you bet $5 and lose, then bet $10 and lose, then bet $20 and lose (doubling your bet wth each loss), after those three hands, you'd have a total loss of $35. So on the fourth hand, if you bet $40 and win, you're back to where you started plus $5.
The basic idea of positive progression is to "parlay" your winnings into winnings of a greater magnitude. So, for example, if you were to bet $10 and win, then bet $15 and win, then bet $20 and win, you'd have a three-hand total win of $45, instead of the $30 you'd have from flat betting. In theory, it is less risky to bet this way because your bigger bets are with "the casino's money" in the form of prior winnings.
Then, there are hybrid systems that combine some elements of both types of progressions. Between the hybrids and all of the individual modifications that can be made to both the positive and negative progressions, there is an almost infinite number of different "systems".
Negative progressions are risky, with the danger being that you can lose a lot very fast with a long losing streak (or a not-so-long streak if you have a couple of double-down losses or start at a high minimum.) The positive progression doesn't risk losing so fast; but it can mute the effect of your winning, since it really requires a nice streak of wins to be really effective. With no streak or very short streaks, the positive progression doesn't perform as wel as flat betting.
One good system I have used is as follows (assume a $5 table): Bet $10. If you lose, go to $20. If you lose again, go to $30. If you lose again, drop back to $5 until you get a win. Any win, anywhere in the series, is followed up with a $5 bet. If that follow-up bet loses, go back to $10 and start over. If the follow-up bet wins, press it with a $7 bet. Continue to press, $10 - $12 - $15 - $17 - $20 - $25 - $30 etc until you lose. At that point, drop back to $10 and start over.
If you play at a single-deck or double-deck game, you won't have many streaks either way longer than just a few hands. So by setting a cut-off point on the negative progression, you somewhat mitigate the chances of losing huge sums quickly. And it is very possible to get into a situation where the table is chopping back and forth, and you can have something like win $10 - lose $5 - win $10 - Lose $5 - win $10 - lose $5, etc. That way, your stack grows, even as you lose as many or more hands than you win.
If you want to take on a bit higher degree of risk in the negative progression, you can make the third bet $40 instead of $30. Then, as you win a bit more, make the second and third bets $25 and $50 instead of $20 and $40. Then add a fourth bet at $100, etc, as you feel comfortable. But be careful that you don't bet more than you'd be willing to double or triple on one hand, because you never know when you'll need to split and/or double-down.
If you want to be more aggressive on the positive progression, that is fine too. Jump from $5 to $10 and then add 50% on each win. I actually prefer to get more conservative on the positive progression, going back to $5 after each couple of wins.
The point is that you can work it any way you feel comfortable. And, although the math is against you overcoming the house edge in the long term, it is certainly possible to turn a nice profit in the short term; and the short term can last a nice little while.
My other advice would be to practice whatever you're going to do on the smulator on this site, or on some other software. You wantt o get the feel for it yourself, not take anyone else' word for it.