Editing Records as You Enter Transactions
In NetSuite, some fields on transactions pages have an open icon 
next to them. Click the open icon to view the selected record in a new tab. In the new tab, click Edit and make changes as needed.
For example, when you are entering a sales order you may want to enter a new phone number for the customer. On the sales order, select the customer and then click the open icon. On the open customer record, click Edit and enter the new phone number. Then click Save. The changes you make to the open record are included in the sales order you are entering.