Create a new database and import the file database_layout.sql into it, this should contain everything required to get started.
To make your server use your MySQL database, edit your settings.xml to at least contain the following settings - of course, replace the example values with the MySQL data to connect to the server.
<settings>
<!-- MySQL Configuration -->
<setting name="@sql.user" value="username"/>
<setting name="@sql.password" value="password"/>
<setting name="@sql.database" value="database"/>
<setting name="@sql.hostname" value="localhost"/>
<setting name="@sql.port" value="3306"/>
<!-- Registration -->
<setting name="@players.allow_registration" value="1"/><!-- Change to 0 to disable registration and show an error message -->
<setting name="@players.registration_error_message" value="Edit this to show the user a message when registration is disabled"/>
</settings>
To get started, clone either the main repository or your fork into mods/deathmatch. It should already come with all configuration files required.
If you are using a linux server, edit your mods/deathmatch/mtaserver.conf and replace
<module src="mta_mysql.dll"/>
with
<module src="mta_mysql.so"/>
You need to copy the file mods/deathmatch/modules/libmysql.dll to your MTA Server directory (the one with MTA Server.exe in it)
Assuming your MySQL connection details are correctly set up, all left to do is to start the MTA server. Otherwise, the server will keep shutting down on startup, look at mods/deathmatch/logs/server.log for a detailed error message.