Before anything else, go out to eat or something to celebrate
After 3, buy something permanent for the house both you and the GF (if she exists) have been wanting (TV, sofa, etc); this will serve as a tangible reminder that you were responsible with the winnings
Real answer:
I’ll add:
4: Go in to debt for more drugs
Druggies
yeah this is the answer but people with suddenly $18,000 from a lottery aren’t going to do it