Can anyone advise how I can acheive this?

I want to be able to select a number of cells, paste the value of 1 into the
cells and change font to bold, with background of yellow

I have been able to do this with the following macro however it will only
paste the value "1" into the first cell, the formatting is applied to all
the selected range, however I want it to paste 1 into all the cells I have
selected

ie I select 1R x 3C run the macro below it will place the value of 1 into
the first cell and then applies the formatting to the 3 cells, I want the
value in there as well?

Hope this is clear
TIA
Michael

' Full_day_Hol Macro

ActiveCell.FormulaR1C1 = "1"
With Selection.Font
.Name = "Arial"
.FontStyle = "Bold"
.Size = 8
.Strikethrough = False
.Superscript = False
.Subscript = False
.OutlineFont = False
.Shadow = False
.Underline = xlUnderlineStyleNone
.ColorIndex = xlAutomatic
End With
With Selection.Interior
.ColorIndex = 6
.Pattern = xlSolid
.PatternColorIndex = xlAutomatic
End With
End Sub