I treat my cannabis plants just like I treat my legumes, corn, and all my other garden veggies. None of these would I ever pre-germinate in a paper towel or soak for extended periods of time. In some regions, these methods work fine, but in others they can lead to seed rot. I wouldn't dare risk my heirloom tomato seeds to these methods, let alone my cannabis seeds, but that's just me.
I simply get a good quality potting mix that is specifically formulated for germinating seeds. My go to soil happens to be (gasp!) Miracle Grow Seed Starting Mix. Never mind what you've heard about the evil MG company. The truth is, their seed starting mix is very consistent from batch to batch, it's available everywhere, it's cheap, and it works. Largely because it's so simple. After all it's just peat moss, perlite, and a tiny tiny amount of fertilizer that's so miniscule it wouldn't even burn a baby lettuce plant. Where people mess up -- be it with Miracle Grow or even Fox Farm -- is they'll buy the richer soils (e.g Ocean Forest) for seedlings when the manufacture clearly states they are for established plants. -- If you want the best start, pick a soil made for seeds. You can always transplant to the richer soils 3-4 weeks post germination.
Once you have your soil, you want to saturated it really good. Some people like to use fancy alkaline reverse osmosis water. Waste of money if you ask me. Good old city tap water has always worked on my lawns and veggies. If a specific cannabis strain can't handle simple tap water, then I don't want that strain anyway. It's a cheap horribly breed strain that doesn't deserve to be kept alive. Back to the soil... I saturate it good, then let it sit for a few minutes, so the excess water can drain.
While the soil is draining, I take a cup of water, drop my seeds into the cup, and let them soak for about five minutes. If the seeds are going outside into the garden, I'll take the wet seeds out, lay them on a paper towel and sprinkle mycorrhizae inoculant, then roll the seeds around. Once this is done, I go back to my containers fill with the potting mix, make a hole with my finger that's about a half inch deep (or 3x the length of the seed), drop the seed in (this is called "sowing"), and I pinch the soil close. Often I'll follow it up with a few quick mists of water, from a spray bottle that has a very fine mist setting. I only spray enough to seal the hole. I want to be careful not to saturate to the point that the seed gets pushed deeper down into the potting soil.
The last step is to place them under my lights or directly outside. If you do it outside, it's actually better because creates a hardier plant, but you want to put a protective screen over them to prevent small bugs from eating the seedlings when they first sprout. However, starting indoors under lights allows you faster germination and you can easily get a couple months head start on your growing, which is how you get monster sized plants.
I happen to use a 200W CFL with a hydrofarm hood. It allows me aprox 2 months of growth, but I usually only do one month because of grow room size restraints. I prefer lights over a heating pad, because pads can short out or get to hot. I also like to leave the lights on all the time (24hr) until the seeds sprout. The reason is that when you rely just on a heating pad or put them on top of the fridge, it could be hours or days before you noticed they sprouted. This is the leading cause of seedlings having excess stretch. If you simply put them under lights now, the moment they sprout they get the light they need, so they stay short, and start off right.
Once they do sprout, I like to switch the lights to 18/6. Its not a hard rule, but it's a pretty good trade off. However, right before I take them outside, I find it's a good idea to change the light schedule to match the outside light cycle. This is especially true with Sativas that can be more prone to early flowering. If you want large plants, avoid early flowering.
This is my method. It has worked great for millions of gardeners and farmers throughout the world for decades. I'm sure it'll work for you as well.
