How do I include my online earning on my tax return?

You can earn up to $600 per site before you have to pay income tax on the earnings. If you reach that level, the site will send you a tax form showing the amount you have made. A lot of them ask for a business id or social security number so the proper form can be sent to the government. If you only earn a few dollars here and there, I wouldn't really worry about it, but you can call the IRS with any questions or your tax person.

I ould suggest you phone up the revenue and customs and ask for their advice as it's best to get your return right first time..