Leaving your hand on the mouse
I can't count the number of stupid, idiot moves I've made online that I would NEVER make in real life. The reason is that I sometimes leave my hand on the mouse when I play. Doing so greatly increases the liklihood of impulsive vulgar moves.
Think of it this way -- touching the mouse is like reaching into the bowl of stones. And since the good habit is: "don't take a stone from the bowl until your move is decided," the same is true for the mouse.
Actually I do tend to leave my hand on the mouse on KGS, because the client will put a little shadow of my piece there and sometimes it makes it easier to see implications of connections, liberties and such. Of course, I'm also very much a beginner, so I haven't quite got the entire visualization thing down. -- Remillard
One good way to rectify this bad habit is to obtain some handy object to hold while considering one's move. I have tried several items, including a squeeze ball, Chinese health balls, a string of beads (useful for checking a list of playing principles, in the manner of a rosary) and a large pebble that I found on an Irish beach. When you decide your move, put down the object and enter it with your mouse. If this method halves the number of impulsive blunders you make each year, then you will win significantly more of your games, guaranteed.
I note that Cho Chikun uses a "hand pump" (according to MSO World's report on the 2000 Meijin-sen), and I have seen Ryu Shikun twirling health balls in his hands while playing against O Rissei in the 2002 Kisei-sen. Such objects not only guard against impulse playing (not that Cho or Ryu would be very likely to do such a thing), but also promote relaxation and relieve stress. -- Tamsin
I've taken to using a paper fan. In addition to blocking impulsive moves, it makes me feel like Sai. -- Scartol
It is not a good idea to have a paper fan when playing IRL (In Real Life): Some people start to repeatedly open and close it, when they become nervous during game. -- juhtolv
What I do is put the mouse on a played stones so if I click it dosn't make a difference (anyoumous)
Phelan: That can still focus your attention in one part of the board instead of another. I prefer moving it out of the board altogether.
This seems to be a controversial subject. While some people discourage holding items such as fans because they promote fidgeting, many high level pros are rather animated with the fans they hold, tapping themselves on the other hand, the leg, or even the head. See sensu for more on this.
Personally, when I play online, I play with a pen that I twirl around my fingers, via penspinning. http://www.youtube.com/watch?v=rihVXhUlHeE
However, I drop my pen quite often, and therefore don't do this in matches over a real goban, seeing as how a dropped pen would disturb the stones, and likely damage the goban.
Consequently, I often end up grabbing a stone before I am ready to play, and after a short hesitation while I study the board position, dropping it back in the bowl. I feel this is worse than fidgeting, because it shows doubt in one's original move, and feels similar to DanglingAStoneAboveTheBoardWhileThinking. --damien