Notes/Domino 4 and 5 Forum

I am new to Lotus Script and need to write a script to save the current document, change one date, save it again, and so on up to a number of times specified by the user in a field called Nbr. The change in date will either be by 7 days, 14 days, or will need to be entered in an input box. There are three fields on the form that ask the user Yes/No questions to determine which method needs to be used. I think I understand how to write the loop and the Select...Case portion. What I don't understand how to do is to save and change the documents. I would appreciate any help anyone can give. I have tried to search for answers but have not been successful. Thank you.