Using WF4 to create Sequential workflow

Hi,

How to create a XAML based sequnetial workflow

I am looking for something like the below however in the XAML model:

http://blog.karstein-consulting.com/2011/03/30/walkthrough-creating-a-simple-sequential-workflow-with-a-custom-task-form-in-sharepoint-2010-using-visual-studio-2010-part-2-of-2/

I mean, options for "CreateTask", OnTaskChanged event, CompleteTask

How to achieve this?

Thanks