Saving Documents as Drafts 
In SAP Business One, you can save sales and purchasing documents, payments, checks for payments and inventory documents as drafts. This allows you to process them at a later point in time.
Procedure
Select the document you want to save as a draft.
Specify all required data.
On the menu bar, choose
File 
Save as Draft 
or right-click in the document window and choose Save as Draft.
Example
A customer phones to order certain items. During the conversation, you enter the sales order in SAP Business One. If, however, the customer does not reach a final decision on whether to issue the order, you cannot add it. You save the order as a draft and process it when the customer has decided to purchase the items.
You create a quotation for a customer. Since this is a large project, you work together with some colleagues to prepare the quotation. Each of you is responsible for a different area of the quotation. You want to define the quotation data at an early stage to ensure that you and your colleagues can access the current quotation when required. You save the quotation as a draft to ensure that you can work on it until all the different areas have been completed.
Note
This function is not the same as a release procedure. You can also define a release procedure for sales documents in the system so that they are not posted in the system and subsequent activities are not carried out until the documents have been released.