PAYE worker additional income with expenses

I did a few nixers last year and made a (small) bit of extra money, we're talking like 3000/4000 - but I did accounts last week and realised that the cost of doing the business resulted in me making a loss. Tools, resources etc. I have receipts for everything to prove I made about €500 loss. What do I do? Do I just declare the income, or declare the income (and expenditure) thus showing the loss?

Any help would be welcome.

You can declare the gross income and the net loss on section 10 of your Form 12 tax return.