Newbie & lost, I need some help

Hello everyone,

I am from Spain. Since I arrived in UK one year ago I am working in a company in a full time graphic designer position. So easy because I don't have to think in the taxes I have to pay or what papers I have to do, everything is done.

Now I have the possibility to do two small graphic jobs in my free time. I have calculated that one of them won't be more than 90£ and the other no more than 175£. And of course I have to give them an invoice for each job. But like I said, this is not a permanent freelance job. Maybe I won't work again like a freelance for the rest of the year.

And now what I have to do? For what I read I think I have to register me like a self employed and then I can create the invoices I need for the work. After that I have to pay my taxes and because it is a small job I can apply for exception to pay Class 2 contributions (I've already paid for National Insurance in my full time job). Is everything correct?

And the questions:

1.- How I know the taxes I have to pay in each invoice and in total?

2.- When I have to pay the taxes if I going to register now? This year 2004-2005 or the next one?

3.- Have I to pay the taxes before or after 5th of April?

4.- When I have to apply for exception to pay Class 2 contributions (CF10)? Before or after the 5th of April?

5.- And when I am finished the work what do you recommend me? Stay registered like a freelance or withdraw it? I understand that If I stay registered like a freelance without earn money I don't have to pay nothing (because of the exception to pay Class 2). Is that right?

Sorry for my silly questions and thank you for everything!