Mind sharing details on what you mean by "preparing"? Like .. a weekend worth or a lot more? I go into interviews with a half day of prep and admittedly it isn'

Mind sharing details on what you mean by "preparing"? Like .. a weekend worth or a lot more? I go into interviews with a half day of prep and admittedly it isn't always pretty. How does someone with a high responsibility/workload current job get the focused prep time? A friend of mine said "3 months to prep for a Google interview" ... I couldn't believe him.