Add 1 to font size of entire worksheet

Is there a way to write a macro that will go throught a worksheet and add 1 to each cell's font size used in that worksheet? I have different fonts and sizes on the worksheet so i cant just select all and change it globally.

my guess is it will looksmilar to this but i am not sure how to do it:

For Each Worksheet In ActiveWorkbook.Worksheets
With Cells.Font
.Size = (current font size) +1
End With
Next