<?php

$apiUser = 'api_user'; //The api user name you created in magento
$apiPassword = 'password'; //The api password
$wsdlUrl = 'http(s)://your-magento-domain/api/soap_v2?wsdl=1';


$soapClient = new SoapClient($wsdlUrl);
$apiSession = $soapClient->login($apiUser, $apiPassword);

$params = array('filter' => array(
    array('key' => 'status', 'value' => 'pending'),
    array('key' => 'customer_is_guest', 'value' => '1')
));
$result = $soapClient->salesOrderList($apiSession, $params)

//End your session
$client->endSession($session);