You can use this function to place subscription form in your theme:
knews_plugin_form( array('id'=> 0[or mailing list id], 'name'=>'ask', 'surname'=>'required', 'stylize'=>[0|1], 'labelwhere'=>'outside|inside|none', 'subtitle'=>[0|1], 'requiredtext'=>[0|1], 'terms'=>[0|1], 'script'=>[0|1]) )