Giving 100% and beating Palermo and Cagliari, without thinking at all about City and Inter, or saving energy for those matches, is a must do.
Despite the awful start, we can and we should still come second in Europa League, even if we lose in Manchester. No need to prepare from today for that match. Play Palermo and Cagliari as if we don't even have a match vs City.
Even if we play with 60-70% of our potential against Palermo and Cagliari in order to have 100% in Manchester and Meazza, chances are that we won't win those two matches and we will risk not winning against the Sicilians and the Sardinians either. It's matches against teams like Palermo and Cagliari that will decide our season, so go with everything we got there and think about City and Inter only when the time comes for that.