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The required fields are: Company, Contract, and Entity.
The "Proforma Invoice (create)" form. The Main tab
In the Company field, select a customer, an individual or legal entity, for whom the document is created. Select it from the Companies list.
The Contract field is populated automatically with the default contract of the selected company. If necessary, you can change it by selecting the contract from the Companycompany's Contracts list contract list (to open the list, select Show all in the drop-down list).
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In the Entity field, select the legal entity of your company for which this document is being prepared. The Entity field is available if the Multi-Company Accounting option is selected on the Administration > Settings > General Settings form. The default entity for all users can be selected on the General Settings form. Also, you can specify your personal default entity, for details refer to Personal Settings.
The Basis field is filled in automatically, if the Proforma Invoice was generated based on a document of the following types: Quotation, Invoice, or Customer Order. If needed, you can manually select the basis document from the list of customer documents (for this, click Show all from the drop-down list). Once the basis document is selected, the data is copied to this Proforma Invoice. If, after you edited the Proforma Invoice, you want to cancel the edits, click the Fill in ( 
) button – the details from the basis document will be copied to the Proforma Invoice.
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The Project field is available if the Project Costing functionality is turned on on the Administration > Settings > Project Costing form. You can link the Proforma Invoice with a project from the list of available projects. If the items in this document are associated with different projects and you need to specify different projects for different items, you can move the Project field from the Main tab as a column to the table on the Inventory and Services tab. For this, use the Settings button on the toolbar (for more information, see Document Toolbar).
If the Enable Project Tasks option is selected on the Administration > Settings > Project Costing form, you can link the entire document with a specific project task or document's line items with multiple project tasks. By default, the Project Task column is available on the Inventory and Services tab. If needed, you can move it to the document header (the Main tab). For this, use the Settings button on the toolbar.
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Notice the hyperlink below the Basis field – AED* Retails* VAT Applied* Prices include VAT on the screenshot above (can be different in your document). By clicking the hyperlink, you can open the Prices and Currency dialog box and change the price-related and tax-related settings for the document. For more details, refer to The Prices and Currency dialog box.
The document totals and other information
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Use the Settings button to invoke the Document Settings dialog box that can be used to move the Project or the Project Task field from the document header (the Main tab) as columns to the table on the Inventory and Services tab or back.
The Document Settings dialog box
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For other button descriptions, see Document Toolbar.