How to make “more” or “continue reading” links on excerpts nofollow?

In your theme’s functions.php:

/* Returns a "Continue Reading" link for excerpts, with 'nofollow' set */
function your_theme_continue_reading_link() {
    return ' <a href="'. get_permalink() . '" rel="nofollow">' .
        '<span class="meta-nav">&rarr;</span> Continue reading</a>';
}
/* Replaces "[...]" (appended to automatically generated excerpts) */
function your_theme_auto_excerpt_more( $more ) {
    return ' &hellip;' . your_theme_continue_reading_link();
}
add_filter( 'excerpt_more', 'your_theme_auto_excerpt_more' );