Sequence diagram for online ordering system

[zoroman]

Hi,
I need to design a sequence diagram for the online ordering system that I will built.
This is how the system works:
-Customer displays the web page, browses the menu and adds items to the shopping basket
- once she wants to checkout, either she has to login to retrieve the contact details from the database or she has to enter it
-and if she is not already logged in she can enter a password to register while she is entering her contact details(but this is optional).
-If she wants to pay by card it forwards to paypal and gets confirmation from paypal and produces a order number to the customer or if she wants to pay by cash then it just completes the order and produces an order number to the customer.In order to pay by cash the amount should be less than £25.

You can download the png format of the diagram that I done from here
http://www.mediafire.com/download.php?jrzmzwnmndo

waiting for your comments
thanks

[darkagn]

Hi zoroman,

Sorry but we aren't allowed to just do your homework for you. Perhaps you could show us what you've tried or discuss how you think the problem should be tackled. We would love to help, but we need to see some effort first.

[zoroman]

Hi zoroman,

Sorry but we aren't allowed to just do your homework for you. Perhaps you could show us what you've tried or discuss how you think the problem should be tackled. We would love to help, but we need to see some effort first.

Well I have included the diagram that I tried to do. There is the link. Let me know if the link is not working...but it should.