At first, what’s most likely to occur is that either your mind wanders away from the subtle pleasant sensation or the pleasant sensation itself goes away. If your mind wanders away, as soon as you notice this, return immediately to the pleasant sensation. But if this wandering away is happening repeatedly, it’s a sign of insufficient concentration; therefore, return to the mindfulness of breathing or whatever other access method you were using, regenerate access concentration, and stay longer in access concentration before once again turning your attention to the pleasant sensation.
