There are two tried and tested methods to successfully germinate cannabis seeds:
Video Cannabis Seed Germination
Take a small plate and lay a layer of tissue paper down - toilet paper will do nicely! Moisten this by soaking the tissue (and running off the excess water) and then place your seeds on top.
On top of this add another layer of tissue paper and soak. Place in a warm dark place and make sure your tissue paper stays moist. Your seed should germinate in 1 – 4 days.
Drop your cannabis seeds into a glass of water (always avoid using chlorinated water) and place in a warm dark place for up to 36 hours (if they have not germinated in that time, revert to the tissue paper method).
For both methods, it is important to pay attention to temperature. If it is too cold this may stop your cannabis seeds from germinating.