calling static methods

[LiteUponLite]

i've the following code and I want to call in the first function the ParserHelper method without instantiating an object (Form1 f=new Form1() ), how to do that?? The declaration of ParserHelper is as follows:
public String ParserHelper (String fileName, String num, String headers)
I tried making it static and then calling it but it gave me errors. So how shud i do it correctly??

namespace HL7Convert
{
	/// <summary>
	/// Summary description for Converter.
	/// </summary>
	
	class HL7Convert
	{
		
		class HL7Viewer
		{
		
			public String Parser(String fName, String fNum, String header)
			{
				Form1 f=new Form1();
				return (f.ParserHelper(fName,fNum, header));
			}
		}

		public  String HL7 (String fileName, String fileNumber, String headers)
		{
			HL7Viewer c = new HL7Viewer();
			return c.Parser(fileName, fileNumber, headers);
		}

		
		public static void Main() 
		{
			String text;
			HL7Convert ct= new HL7Convert();
			text=ct.HL7("test.txt","324", "st tt ");
			Console.WriteLine(text);
			Console.ReadLine();
			
		}
	}
		
	
}