Originally Posted by Maddy

I used to work for the dreaded IR and you could probably get away with it. Otherwise if you are going to do it legitimately you have to register within three months of starting out. If you are employed and paying Class one national insurance contributions you won't have to pay class 2 contributions. If you don't expect to earn much from self employed work in a year you can declare this and be exempt from paying class 4 contributions so you only have to pay tax on you profits which if you keep any graphic design related receipts will bring the profit down (whether or not it was for the self employment).

But if it were me and it wasn't for much work, I'd do it cash in hand. You can still create a VAT free invoice but you just won't be doing anything at your end and is really for the customer's books.