<form method="get" role="search" action="<?php echo esc_url( home_url( '/' ) ); ?>">
  <input type="text" aria-label="<?php esc_attr_e( 'Search for', 'pally' ); ?>" class="search-field" name="s" placeholder="<?php esc_attr_e( 'Search term', 'pally' ); ?>" value="<?php echo get_search_query(); ?>">
  <button type="submit"><?php esc_html_e( 'Search', 'pally' ); ?></button>
</form>