Critiquing is allowed and encouraged, but do not rip into anyone's content.
Consider using the sandwich method.
Give positive reinforcement via a compliment. Then share criticism on what can be improved and how. Finally, end on a high note with more compliments.
Use the “I” language strategy.
Using phrases like “I think,” “I feel” and “I’d suggest” makes sure that the person receiving the feedback understands that the criticism is about the situation or behavior rather than about them as a person.
Focus on the action or behavior.
When delivering constructive criticism it is important to focus on the specific action, outcome or behavior that you would like to see improve. Similarly, when focusing on the action and improvement you would like to see, consider using non-specific language such as “the build,” “the ability” or “the project” rather than “your build,” “your ability” and “your project.”
Include specific positive praise.
Offer specific praise for a member's build, color/block choices, ability to overcome an obstacle, or another success or achievement that was done well. This allows them to focus on the things they do well. Then, they can apply those strengths to plans of improvement you may implement for weaker skills or performance. Additionally, praising your employees often and when merited can increase employee morale and motivation.
Provide actionable feedback.
When implementing constructive criticism, it is important to offer feedback that someone is able to put into action immediately to achieve new objectives and increase their motivation/creativity.
Use empathy.
An important key to constructive criticism is empathizing with the person who is receiving the feedback. Put yourself in their position and think about how you would want to hear the criticism and what specific words would be most helpful to you.
Read more about these methods, and see examples of each.