There is no doubt that the reason for my awful oversight was over-confidence that sapped my sense of danger. So that is where to look for the cause of bad blunders - in the exulting feeling of self-congratulation.

You must not let your opponent know how you feel.

Drawing general conclusions about your main weaknesses can provide a great stimulus to further growth.

All candidate moves should be identified at once and listed in one's head. This job cannot be done piecemeal, by first examining one move and then look at another.

Time trouble is blunder time.

If your opponent is short (on time), play just as you played earlier in the game. If you are short keep calm, I repeat, don't get flustered. Keep up the same neat writing of the moves, the same methodical examination of variations, but at a quicker rate.

If a chess statistician were to try and satisfy his curiousity over which stage of the game proved decisive in the majority of cases, he would certainly come to the conclusion that it is the middlegame that provides the most decisive stage.