Try to get on the TPC (technical program committee), if possible, that is better for you to boast about. Your efforts to review 8 papers are already what a TPC member would contribute anyway. Review really has no definite requirements. Probably different fields are different in this requirement as well. You may read what others reviewed about your papers, and do the similar thing. For myself, I typically write in this 八股文: 1. What I understand about this paper on its purpose and result. Which part is new, good, or promising, etc. This is so called "praising" phase. 2. What questions I have about the paper, which parts are not clear, or need more experiments, what comparison (with other algorithms, or on different datasets, etc) I am expecting, etc. This is so called "criticizing" phase. 3. Regarding the structure, grammar, and general presentation, I may say a few things, point out the typos I've noticed, etc. Finally you need to make a decision, just follow your judgement, accepting or rejecting is both okay.