1) Your web service will need to have a complete set of methods for working
with your database table (retrieval, update , deletion, insertion).

2) You create a class that contains properties representing the fields in
your data table

3) You create a class that will have methods for inserting, deleting,
retrieving and updating the rows in your database table. Those methods will
accept objects of the class created in step 2 as parameters and will be
wrappers around your webservice calls.

4) Within your application, you can use a
System.Web.UI.WebControls.ObjectDataSource linked to your classes
(DataObjectTypeName property will be the name of the class created in step
2, TypeName property will be the name of the class created in step 3)

You should have a look at ObjectDataSource in MSDN for specifics and further
details.

HTH,
Cois