Step 1: Gathering the Proper Materials
1. A Mouth, and the ability to speak
2. Friends or colleagues to criticize, constructively of course
Or, if you're a Internet Tough Guy, what you'll need is:
1. A computer and keyboard (sometimes a mouse is helpful, but not always mandatory)
2. A pair of hands to type with
3. Fewer compliments are needed for this option
Friends are optional
Step 2: Offering Constructive Criticism
Always remember to be as kind as possible even if their work isn't the best. Always use the compliment sandwich form of criticism, start with a compliment or something good, next tell them something that they could improve on, and finish with a compliment.
Here's a video of how NOT to offer constructive criticism:
Note the raised voice and raised chair. Some may find this a threat. You may see it as a joke, but some see it as bullying, and bullying is BAD.