On fly!
Leave the column with sum as it is. Add an empty column next to it, with formula like
Code:
= "" & Q6 & "+" & R6 & "+" & S6 & "+" & T6 & "+" & U6
NB! The added column displays all components of sum as string! You can take it as comment of formula.
And in case the components of original sum are formulas instead cell references, like:
Code:
= SUM(Formula1,Formula2,Formula3,Formula4)
in added column you use formula:
Code:
= "" & Formula1 & "+" & Formula2 & "+" & Formula3 & "+" & Formula3 & "+" & Formula4