I just talked about some that the Buddha taught his son, Rahula, in the Rahulovada Sutta. He told Rahula to ask himself: does this lead to my own affliction, to the affliction of others or the affliction of both? Is it a skillful action, speech or thought, bringing happy consequences and happy results?
These are very important questions we have to ask ourselves about our speech, our thoughts and our actions. As far as asking others, we may need to be a little bit more cautious in our approach. But as far as asking ourselves, it's quite important for us to be truthful to ourselves, because often when we are not so direct with ourselves, we get very skillful in justifying our unbeneficial actions, speech and thoughts.