com;any formation uk,company formation london,company formation birmingham,company formation reading,company formation mangester

If you are a sole trader you are working for yourself. You will need to first inform the HMRC that you are self-employed at least within 3 months of being self-employed. You need to use form CWF1 to notify HMRC. You will need to maintain your books of accounts, file your income tax return called Self Assessment, pay VAT (if applicable). If you employ people you need to manage payroll, pay salaries, taxes and NI. You will also register with the HMRC for the Construction and Industry Scheme (CIS) as a sub-contractor or contractor if you are doing works in construction. 
https://www.globalcompanyformation.co.uk/