I'm stuck on step 4 of the simple sitemaps for multisite plugin….

This is what I see when I open .htaccess:

RewriteEngine On

RewriteBase /

RewriteRule ^index.php$ – [L]

# uploaded files

RewriteRule ^files/(.+) wp-includes/ms-files.php?file=$1 [L]

RewriteCond %{REQUEST_FILENAME} -f [OR]

RewriteCond %{REQUEST_FILENAME} -d

RewriteRule ^ – [L]

RewriteRule . index.php [L]

Am I typing in this code: RewriteRule ^(.*/)?sitemap.xml wp-content/sitemap.php [L]

And if so, where exactly do I put it?