Can I register myself as self-employed even before I take on any freelance jobs?

I may take on some side hustles (in addition to my full-time job which will be PAYE). Can I start registering myself now as self-employed even if I don't have any freelance jobs now yet and may not have at the end of the tax year? If so, do I then report no profit (and no cost) in the self-assessment tax returns form? Thanks!

Hi I,

If you are likely to earn self-employed income during the current tax year, you should register now for self assessment.
In the event that you in fact earn no self-employed income and incur no expenses, you should complete the Self Employment pages (SA103) accordingly.
Register for Self Assessment

Thank you.