You know the most common question I get asked is, "Please let me know when the price drop, because I want to buy in when the price is at it's lowest" So they ask me to tell them when the price is low, because they do not monitor the price every day.

Just make sure you explain the pros & cons to them and highlight that Bitcoin investments is a very high risk investment. After you have done that and they agree to take full responsibility for their own actions, then you can advise them on when the right time for buying is.