I'm a web developer living in the UK.
Last September I found one client in the UK that was looking for web developers for his websites. Since September he has been paying me monthly on the basis of tasks that I've done.
I'm registered as a self employed and I have an UTR number. Should I issue invoices for his payments? Should I charge him VAT or something else in the invoice? Or do I just send him a simple invoice with the date, description and pay?