Look at all these questions and think of possible answers. They can help you to structure your monologue, or if you prefer, you can also use them as prompts to speak with your partner in a dialogue form. Lots of conditionals!!
How much do you spend on the lottery?
Do you play regularly or just occasionally?
What prizes have you ever won?
Has anyone you know won the jackpot or a big prize?
If so, did their life change?
What would you do if you won the lottery?
How much of the money would you save, spend and give away?
Would you try to keep your name secret?
If so, how can you achieve that?
What do you see as a disadvantage to winning the lottery?
How would you deal with situations like strangers approaching you for money?
Do you think it is possible to win hundreds of millions of dollars and keep your personality, values and outlook on life intact?