one way:
you shold open the template file for reading, and replace some `keywords' with some vars.
for example, I'll replace PUNTO_USERNAME with $user_data['username'], and 'PUNTO_PASSWORD' with $user_data['password'].
// $mail_template = path_to_template_file
$f_d = fopen($mail_template, 'r');
$mailBody = '';
while ( $line = fgets($f_d, 2048) )
{
$line = str_replace('PUNTO_USERNAME', $user_data['username'],
$line);
$line = str_replace('PUNTO_PASSWORD', $user_data['password'],
$line);
$mailBody .= $line;
};
fclose($f_d);
PM