The most efficient way to improve your chess is to play lots of games.
The online chess community makes it easy to find opponents of any skill level. This is the reason why the number of great young chess players is much greater today; anybody can gain experience on the Internet, 24/7. In the old days, players had to travel to tournaments to gain the same experience that can now be gained in an online equivalent overnight.
So, you ask, how do I best take advantage of the online chess offerings to gain experience and improve my chess?
First, select a server that is dedicated to chess. More generic game servers that offer a multitude of board games invariably offer a worse experience and a weaker community for the chess fan.
Second, choose a server that has a decent amount of players logged in at any given time, so that you always can find an opponent that wants to play at your preferred time control.
Third, go for an intuitive interface that fits your requirements.
Fourth, depending on your preferences, you will want a server where tournaments are organized and where there is a vivid and well managed community.
The three chess servers I would shortlist are FICS, ICC and chess.com. I do not want to rank them, because they offer slightly different experiences and it is a personal choice which server will best fit you. All of them hosts a large number of players at any time, and they regularly organize leagues and tournaments for both individuals and teams. There are also organizations like Chess Matches HQ and STC Bunch that welcome players from multiple servers. Below, I give a summary of the pros and cons of each chess server.
Pros: Free, Many interfaces are available.
Pros: Many strong players
Cons: Not free ($59.95/year)
Pros: Free, strong community features, no download required
Cons: Not very strong players, bare-bones browser-based client
I play on FICS myself, mainly because it is free and I love the interface. For quick blitz games I prefer the free BabasChess client, which can be a bit intimidating at first, but is very powerful. For example, it supports move announcements and third-party plug-ins.
But I prefer to play longer games, say an hour per game and player. The problem with online chess is that you are using a computer interface, while a part of the chess experience that I love is to play on a standard wooden board with real pieces. The most common solution is to use a DGT board, a standard chess board that connects to a computer via USB (wireless connections are in the works) and allows you to play online chess. This solution is used in all major real-life tournaments to broadcast games live over the Internet. The problem is that investing in a DGT board will require tough financial negotiations with your significant other, the price tag for a standard setup is €479,00.
Isn't there a cheaper solution out there?
Yes, there is! I'd like to share with you the environment I have been using lately. It is a setup that I am very satisfied with. I use a standard full-size wooden chess board, to play my games far away from a buzzing computer fan and a glaring computer monitor. I log in to the chess server using the PocketGrandmaster software (version 4 supports both FICS and ICC) on my Pocket PC. The Pocket PC connects to the Internet via a USB cable to my silent media center that sits in the living room - but a Wi-Fi connection could work even better. When I play a game, PocketGrandmaster says my opponent's moves out loud, so that I don't need to take my eyes off the board. To submit a move, I first move the piece on the real board and then use the Pocket PC’s touch screen to submit the same move to the server. The difference from the DGT board is not huge and the only pain is that I need to make my own moves twice, while the DGT board automatically detects the moves made on the board. But, I can definitely live with this limitation, considering the price difference.