In a worksheet, pick the cells you want to be in a designated range.
In addition to the row or column labels, choose the range you want to designate.
Go to Formulas > Create from Selection by clicking.
Select the appropriate checkbox in the Create Names from Selection dialogue box based on where your row/column header is located.
Choose OK.

Create a named range in a worksheet by selecting cells.
Choose the range to name, including the row or column labels.
Select Formulas > Create from Selection from the menu.
Select the checkbox (es) depending on the location of your row/column header in the Create Names from Selection dialogue box.
Select OK.