The following spreadsheet is just a sample and quite easy tool for printing and completing packing slips. It was created to be accompanied with purchase orders and sales invoices.
If you want to update or improve your template, you are free to copy the worksheets and attach it to sales invoices workbooks or link cells. So that when you are creating new invoices, you could use already created slips.
You can use these templates at your business and update slips according your needs. Sign and attach them to sales or purchase invoice.