Before the review, perform a simple exercise. Identify the 3-5 things you are really good at, things you consider to be your core competencies. Describe the behaviors, skills and proficiencies you have that support why you excel in these areas. Provide credible backup and business results that support your competency claim.
Often times, your manager isn't as close to your projects as you are and this is an opportunity to highlight in detail what you did. General statements can downplay your accomplishments.