The settings in the Identities page are fairly straightforward. Select the default identity and click Modify.... Fill in the Your name field with your full name (e.g. John Doe) and, optionally, the Organization field with the appropriate information.

Next, fill in the Email address field with your email address (e.g. [email protected]).

That is all for this dialog unless you want to use the more advanced features (cryptography, a signature, etc.). You can find more information about these features in the full KMail manual. Click on the OK button to close this dialog, and move on to the next configuration page...