The best way to write a review on any product is first to use the product and then write a review then only you can direct the people what to buy and what not.
PLEASE READ THE ENTIRE REVIEW TO UNDERSTAND WHATS NECESSARY TO WRITE A REVIEW.
Your review must consist of following
The special features of the product and what is the thing that is attractive in that product. You may even write against the product this is totally up to you did you like the product or not.
Compare it with similar products this makes your point even more strong we you compare it with other similar products and it even guides the reader which product to buy.
The drawbacks of the product you must tell your readers about the good as well as the bad points of the product this will make your review more interesting because readers will find that you are not just showing the good side but the overall review.
Your experience with the product you must mention an incident when you realise that this product was very useful or very bad this makes your points more specific.
Your review must be upto the point and bierf dont think writting to many words can attract readers they will just get bored and quit. So keep it small and specific.
Give and overall review and surely mention all the features this is the most important part after reading this the reader will either rate your review or leave comment so be more attractive at this part.
If you find this helpful then please like and surely comment if you want to know anything or if you find any mistakes or any room for correction.