Giving positive advice to people who are open to hearing it, is one of the greatest acts of kindness you can do.
Be careful not to give advice when it is unwanted, even if you are well-meaning. A prerequisite for giving advice is to have the humility not to give advice unless you are certain it will have a positive outcome.
How you give advice is often a key factor in whether or not it will be appreciated. Giving positive advice takes great skill.
Sources: For a series of probing questions on this topic, see Rabbi Zelig Pliskin’s “Gateway to Self Knowledge,” pp.104-6