Hi,

I have a criminal conviction for possession of a class A drug for which I received a fine, this happened around 10-15 years ago and I have not been in trouble before or since that.
 I have provisionally booked a holiday to the USA in December. I understand I cannot enter the USA on an ESTA and need to apply for a B2 tourist visa. I am just wondering if anyone can advise me of when to start the process of applying for the visa?

Thanks in advance.