This is a short introduction to KMail and its usage so you can start working with it right away. For more in-depth information see the Using KMail section. Note that KMail's installation is described in the appendix.
Invoking KMail for the first time creates a directory called Mail containing the initial files (inbox, outbox, sent-mail, trash and drafts) in your home directory. Use Settings->Configure KMail... to enter some initial information so KMail will be able to properly retrieve and send your messages.
The Configure window consists of seven sections: Identity, Network, Appearance, Composer, Mime Headers, Security, and Miscellaneous. To begin sending and receiving messages you will only have to change the settings in the Identity and Network tabs.
The settings in the Identity tab are fairly straightforward. Fill in the Name field with your full name (e.g. John Doe) and the Organization field (optional) with the appropriate information. Next, fill in the Email Address and the Reply-To Address (optional) field with your email address. If you are using PGP or GnuPG you need to set an identity in the PGP User Identity field.
Optionally, set the location of your signature file in the Signature File field. If you want a random signature, you may specify a program and check the The file is a program box.
If you add a new identity, an Add Transport... button will appear (this button does not exist for the Default identity). It allows you to configure a way of sending messages for a specific identity, e.g. you might want to use a different SMTP server for one of your identities.