1. Start WeeChat

A recommended terminal emulator for X (but not mandatory) is rxvt-unicode: it has good UTF-8 support, and no problem with default keyboard bindings.

Run from your shell:

$ weechat

2. Online help / options

WeeChat has help for all commands, just issue:

/help

To get help on a specific command, issue:

/help command

To set options, issue:

/set config.section.option value

(where config is configuration name (weechat for core, or a plugin name), section the section of this configuration and option the option name).

WeeChat immediately uses the new value (you never need to restart WeeChat after changes to configuration).

All settings are saved when WeeChat ends (or with /save command to force a write of the options).

Important
 It is not recommended to edit configuration files by hand because WeeChat may write them at any time (for example on /quit) and after any change you must run the command /reload (with the risk of losing other changes that were not yet saved with /save).
You can use the command /set, which checks the value and applies immediately the changes.

Help is available for options:

/help config.section.option

The plugin fset allows you to easily browse options and change them.

For example to display WeeChat options:

/fset weechat.*

IRC options:

/fset irc.*

The /fset command has completion on part of option names, so for example if you type /fset hot and press Tab this is completed as /fset hotlist. If you press Enter, options about the hotlist are displayed.

For more information about /fset command and keys, see /help fset.

3. Core vs plugins

WeeChat "core" is only used to display data on screen and interact with the user, that means weechat core without plugins is useless (faithful users: IRC was part of core for versions ≤ 0.2.6).

All network protocols like IRC are provided in separate plugins.

Use the /plugin command to list loaded plugins, you should see "irc" and other plugins in the list.

4. Add an IRC server

You can add an IRC server with /server command, for example:

/server add freenode chat.freenode.net

In this command, freenode is the internal server name used by WeeChat: you’ll be able to connect with /connect freenode and the server options are irc.server.freenode.xxx.

As usual, help is available if you’re lost:

/help server

5. Set custom IRC server options

WeeChat uses default values for all servers ("fall backs"), if you don’t specify a specific value for a server option. These default options are "irc.server_default.*".

For each server option, WeeChat uses its value if it is defined (not "null"). Otherwise WeeChat uses default value ("irc.server_default.xxx").

For example there are default nicks (based on your un*x login), and you can override them for freenode server with following command:

/set irc.server.freenode.nicks "mynick,mynick2,mynick3,mynick4,mynick5"

To set the user and real names:

/set irc.server.freenode.username "My user name"
/set irc.server.freenode.realname "My real name"

To enable auto-connect to server at startup:

/set irc.server.freenode.autoconnect on

To connect with SSL:

/set irc.server.freenode.addresses "chat.freenode.net/7000"
/set irc.server.freenode.ssl on

If SASL is available on server, you can use it for authentication (you will be identified before you join channels):

/set irc.server.freenode.sasl_username "mynick"
/set irc.server.freenode.sasl_password "xxxxxxx"

To run a command after connection to server, for example to authenticate with nickserv (only if you don’t use SASL for authentication):

/set irc.server.freenode.command "/msg nickserv identify xxxxxxx"
Note
 Many commands in option command can be separated by ; (semi-colon).

If you want to protect your password in configuration files, you can use secured data.

First setup a passphrase:

/secure passphrase this is my secret passphrase

Then add a secured data with your freenode password:

/secure set freenode_password xxxxxxx

Then you can use ${sec.data.freenode_password} instead of your password in IRC options mentioned above, for example:

/set irc.server.freenode.sasl_password "${sec.data.freenode_password}"

To auto-join some channels when connecting to server: