How to return multiple values from a webservice?

I am very new to the world of web services so please bear with me. I am creating a very simple web service in Visual Studio 2010 using .asmx files.

Here is the code I am using:

namespace MyWebService
{
    [WebService(Namespace = "http://www.somedomain.com/webservices")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]

    public class Service1 : System.Web.Services.WebService
    {
        [WebMethod]
        public string simpleMethod(String str)
        {
            return "Hello " + str;
        }   
    }
}

When I invoke this and enter a value "John Smith" for the the str parameter it returns:

<?xml version="1.0" encoding="utf-8"?>
<string xmlns="http://www.somedomain.com/webservices">Hello John Smith</string>

My question is what is the best practice for returning more than 1 value for a web service method? If the values are all the same data type should I use an array? If the the values contain different data types would I need to create a custom class?