You should create a style to apply to the text. This does that for you:
Sub ScratchMacro()
'A basic Word macro coded by Greg Maxey
Dim oRng As Range, oTextRng As Range
Dim oParStyle As Style, oChrStyle As Style
On Error Resume Next
Set oParStyle = ActiveDocument.Styles("Warnings")
If Err.Number <> 0 Then
Set oParStyle = ActiveDocument.Styles.Add("Warnings", 1)
With oParStyle
With .ParagraphFormat
.Alignment = wdAlignParagraphLeft
.Borders.OutsideLineStyle = True
End With
With .Font
.Name = "Times New Roman"
.Size = 12
End With
End With
Err.Clear
End If
Set oChrStyle = ActiveDocument.Styles("Warning")
If Err.Number <> 0 Then
Set oChrStyle = ActiveDocument.Styles.Add("Warning", 2)
With oChrStyle
.Font.Color = RGB(200, 0, 0)
.Font.Bold = True
End With
Err.Clear
End If
Set oRng = ActiveDocument.Range
With oRng.Find
.Text = "WARNING*WG[0-9]{1,}"
.MatchWildcards = True
While .Execute
With oRng
.MoveEndUntil Chr(13)
.MoveEnd wdCharacter, 1
.Style = "Warnings"
Set oTextRng = .Paragraphs(1).Range
oTextRng.End = oTextRng.End - 1
oTextRng.Style = "Warning"
.Collapse wdCollapseEnd
End With
Wend
End With
lbl_Exit:
Exit Sub
End Sub