It is very helpful to create a single translation file for your magento template to include any words or phrases that you add to the basic templates.

Simply create an empty module (create a folder under app/code/local/[yourcompany]/[yourmodule]) and then add a subfolder etc and create a config.xml which should contain the following.

<?xml version="1.0" encoding="utf-8"?>
<config>
    <modules>
        <translations>
            <version>1.0.0</version>
        </translations>
    </modules>
    <frontend>
        <translate>
            <modules>
                <translations>
                    <files>
                        <default>swn_translations.csv</default>
                    </files>
                </translations>
            </modules>
        </translate>
    </frontend>
    <adminhtml>
        <translate>
            <modules>
                <translations>
                    <files>
                        <default>swn_translations.csv</default>
                    </files>
                </translations>
            </modules>
        </translate>
    </adminhtml>
</config>

Make sure your module is enabled (see [Creating your own module][1]). and that’s it.

[1]: #create_module