First, add a link to Redactor's translation on a page, for example for Finnish language:
<script src="/your-folder/fi.js"></script>
Then create a file with the plugin translation and connect it to the page too:
<script src="/your-folder/plugins/myplugin.fi.js"></script>
In the plugin's translation file, call the $R.addLang function to add the object with the language variables to the Redactor's translation. For example:
$R.addLang('fi', {
"table": "Taulukko",
"insert-table": "Lisää taulukko"
});
That's all. Now gathering everything.
<!DOCTYPE html>
<html>
<head>
<title>Plugins are friends, not food!</title>
<meta charset="utf-8">
<!-- redactor css -->
<link rel="stylesheet" href="/your-folder/redactor.css" />
</head>
<body>
<!-- element -->
<textarea id="content"></textarea>
<!-- redactor js -->
<script src="/your-folder/redactor.js"></script>
<!-- translation-->
<script src="/your-folder/fi.js"></script>
<script src="/your-folder/plugins/myplugin.fi.js"></script>
<!-- plugin js -->
<script src="/your-folder/plugins/myplugin.js"></script>
<!-- call -->
<script>
$R('#content', {
plugins: ['myplugin'],
lang: 'fi'
});
</script>
</body>
</html>