How to Start Your Tax Return
The best time to start your tax return is shortly after the tax year ends in April. This gives you plenty of time to gather documents and avoid the January rush when the system often slows down. First, make sure you're registered for Self Assessment.
If you're new to the process, do this by October at the latest, as registration can take several weeks. Log into your HMRC account with your Government Gateway ID and password. From your account homepage, select 'Complete a tax return' for the relevant tax year. Work through each section methodically, answering the questions that apply to your situation.
You can save your progress and return later if needed. The system will guide you through different sections based on your circumstances. These range from employment income to self-employment, property and investments.
I once left my first tax return until mid-January, naively thinking it would take just an hour or two. Three stressful days and several calls to HMRC later, I vowed never to leave it late again!