Using VBA to create column header

I've created some columns using this code:

Private Sub AddNameColumns()
    With Sheets("ModifiedData")
        Columns("B:D").Select
        Selection.Insert Shift:=xlToRight
        Columns("N:P").Select
        Selection.Insert Shift:=xlToRight
    End With
End Sub

I'd like to put values (or column headers) into B1, C1, D1, N1, O1, and P1.