You have to create an XML to call a proper method. After creating the request XML you can use such kind of code.
Every method will return with an XML response.
Get one contact’s details by ID. Define the ID in the contact_id tag.Sample request XML.
Get all of the contacts’ IDs and names belogns to the CO3 account.Sample request XML
Get the possible values of the contact history types.Sample request XML.
Get contact’s history by contact ID.Sample request XML.
Create a new history element for the specified contact.Sample request XML.
Create a new contact. You can send custom fields if you specified them before on the CRM / Settings / Custom fields page. Sample request XML.