How we change what others think, feel, believe and do
You can use assertion both in giving praise and receiving it.
In giving praise assertively, be specific about the other person has done well. Mention the value that the other person has created and how you feel about it.
Make the praise heartfelt. Do not say anything that you do not really mean.
You can praise your superiors as well as peers and subordinates. Many managers receive very little recognition from their charges and a little appreciation can go a long way. Be careful and succinct with this -- it is easy to appear as if you are sucking up to them. A simple way of doing this is to thank them when they have helped you in some way.
When other people praise you, accept it with a slightly surprised thanks.
Do not be arrogant or show that you expected the praise ('Yes, it was rather good, I though'). Nor be excessively diffident, effectively refusing to accept the praise or downplaying your part in it ('Oh, it was nothing, really').
Jed, you did a great job of getting the project completed to schedule. I have had several very complimentary comments from our customers about it.
Michelle, I really liked the way you handled Steve, yesterday. That was a tricky situation and could easily have got out of hand.
Thank you. That's very kind of you to say that. (accepting praise)
Praise is a powerful motivator, if done well. It affirms the other person's sense of identity, increasing their sense of worth. It also tells them what they are doing well. Generally, people will do more of the things for which they are praised, but only as long as they believe that they deserve the praise and that it was genuinely offered and without ulterior motive.
Weak praise can sound like empty flattery, seeking to appease the other person rather than offer genuine appreciation. When you give praise when it is not really deserved, then you make worthless any praise that is deserved. As a result, the other person will never really feel praised (and will dislike you for 'assassinating praise').
Aggressive praise can sound like cynicism or sarcasm that still seeks to keep the other person in an inferior position. It happens when people realize that the other person has done a good job but rather than truly admiring the other person, they feel threatened, and that their own limitations have been shown up (perhaps deliberately).