not to work together...though some could....
the sessions work by button "NEXT' submitting the form and the server taking all the data and storing it in a session variable until needed...then using the session to add the new info from the other remaining forms...
the layers you have correct...clciking the next button causes the current layer to hide and the next layer to be come visible...the last layer will hold the submit button to submit the form will all the data from all the forms...
hth