If you earn casual income (e.g., for babysitting or doing odd jobs) you can report it as “Occasional earnings” in the Tips, Royalties, Occasional Earnings, etc. section.
That said, if you earn a substantial amount of money, chances are you are either earning:
- business income and should report it on a T2125, or
- employment income, and the payer should be deducting and remitting payroll tax and providing a T4.