Keyloggers are nasty spyware tools that spy on your keyboard, they record whatever keys you press over a session and send this data over to someone else. Most of spyware removal tools can do a good job at detecting these parasites, however as any other malicious scripts keyloggers evolve rapidly and sometimes can go undetected. Though there is something you can do to make sure that your most sensitive information(banking login details, credit card numbers) stays hidden even when you got keylogger spying.
Keyloggers can only record keystrokes(in order they have been pressed) but not mouse cursor movements, and that’s how you can mislead them. For instance, if I type 456 and then using mouse take cursor back infront of 4 and type 123, on the screen I will get 123456 but keylogger will record 456123. Or instead of placing cursor infront of 4 I can highlight number 5 and type 123, this way I will get 41236 but keylogger would still record 456123.
Now, lets say your real password is Abc27DeF, to mislead keylogger you can initially enter AQRtDF, then using your mouse cursor highlight QRt and enter bc27 and afterwards place a cursor between letter D and F, and enter e, as a result you will get Abc27DeF however keylogger will record AQRtDFbc27e. I guess you got the idea, so just use your own imagination to make things more complex by doing some inserting, highlighting and substituion. It is also very important that you always use exactly same tactics for each of your data, if you came up with a specific way to enter your credit card number then always enter it that way.
It isn’t something you should use everytime you access your email or myspace profile because doing this multiple times per day isn’t fun at all, so use it mainly for very sensitive details where you can’t take even 0.01% risk.