All the top players study poker away from the game. That is how they continuously beat the games that they are playing. Self study will ensure that your game does not stagnate, will help spot leaks, and will help you spot leaks in your opponent’s games. It is by far the best work you can do away from the table. So before you can start doing hand history reviews it is essential to buy a piece of software called Holdem Manager (before you mutter to yourself, here’s some promotional waffle about Holdem Manager, please let it be known I am in no way affiliated with this product. I wish I was because I love it!).
Holdem Manager is an online poker tracking software which keeps track of every hand you play on line. It allows you to then analyse all those hands and replay them using a hand replayed and give statistical breakdowns of equity and pot odds in those hands. It allows you to study your opponents as well as your own play. It has revolutionised on line poker. It costs between $50-$80 depending on whether you buy the professional or beginner package, but it is well worth the money.
To begin your hand history review, you can filter on a reports tab in Holdem Manager and input all hands played after a certain time period, say over a 2 month period. You can then filter all your hands from biggest pots lost to won. Then start a spreadsheet or just use a refill pad and note how you lost every big pot over 30 big blinds. I guarantee you even with limited knowledge of poker; once you go back over a hand in a replayer you will spot the blatant mistakes easily. Note what the mistake was and move on to the next big pot you lost and rinse and repeat.
Once you have done this you can start to group the mistakes. You will start to see a pattern of where you are making the same mistakes over and over again. In my last big hand history review after a downswing I had 9 mistakes I saw happening way too frequently for my liking. I then put this on a word document and printed it out and read this sheet before I sat down to play a session over the next month. At the end of the month I reviewed my hands played that month and put a line through the mistakes I had removed from my game and highlighted the ones that still remained. I had the list reduced to one and since then I have cut out that mistake from my game and I am currently on a upswing and very happy with my game.
I do believe that once a month you should review all your hand histories of all big pots over 30 big blinds which you either won or lost to keep away those pesky downswings and your game fresh.