1 - start by reviewing stuff you already use and love
2 - make contact with PR reps or directly with the publicity contact for the companies who put out the products you're interested in reviewing (P.S. after a while, you'll start getting contact directly FROM reps who want YOU to feature their products)
The best piece of advice I can give you is to say that the more exposure you have and the more PR reps like your blogging and writing style, the better chance you have of getting contacted directly, and then the product review requests will start trickling in.
Mom Bloggers for Social Good is a global coalition of 2000+ mom bloggers who currently span over twenty countries and who care about spreading the good news about the amazing work non-profit organizations and NGOs are doing around the world. Want to make a difference?Please join us!