Noticing Newbies

Sure. A good place to start would be "Guidelines To Great Reviewing" 

You want to be helpful and positive while telling the person what you like about their work and if necessary where you think it would be improved. These guidelines linked above give you information on the best things to consider, when rating and reviewing.

After a while, you will approach a review with your own flair and voice, and be able to incorporate the things mentioned in the guidelines comfortably.

I hope this helps.