How to praise.
Do it often. Five times a day minimum; 25 times would be even better.
Spread it around your team or colleagues to avoid a sense of favourites.
Remember, it's for their benefit, not yours. This will make it more genuine.
Don't mix praise with negative feedback, otherwise it will not be heard.
Choose the right moment. Broadly, for praise on a minor matter, do it straight away, otherwise it will look like a bigger deal than it is.
Give the context. If the praise isn't offered immediately, it helps to let them know what exactly you are talking about: 'The proposal that you put forward to our financial client last week...'
Explain specifically what went well. The more precise the praise, the more effective it is. By just saying 'Thanks for the report - it was great', you are not giving the other person anything they can usefully apply in the future. Was it great because the report was detailed, had a succinct summary, included good questions...?
Describe the impact it has had. This is the part that motivates. The good/positive consequences that flowed as a result of what they did well are what encourages them to repeat this behaviour.
Describe the skills they demonstrated, or what it tells you about them as a person. This is the part that makes the other person feel really good: 'Thanks for leading the meeting so inspirationally; what a great team of people you have persuaded to get involved in the project.'
Congratulate. This is usually the beginning, middle and end of praising. It has a role but if it's all you do, you get only one star.