[header] How to leave a review on amazon [title] Be sure to test the product thoroughly before writing your review. [substeps] Per amazon's tos, you should have the product at least 48 hours before writing a review. For supplements or similar products, you should wait until they've had long enough to take effect before reviewing. 
[title] Don't intend to review broken or defective products. [step] Instead, try to get a replacement before writing a review.