***I'm somewhat of a new-to-cannabis grower (and I've had humidity issues with seedlings of late). But for what it's worth...***
Part of it will depend of your motivation and objectives. In my case, I approached growing from a long term sustainability perspective; I wanted to recycle my soil which would both save money and reduce the environmental impact of harvesting Peat Moss and shipping. Here was my process;
1. Start with a premixed living soil: There are plenty of examples such as Fox Farms Ocean Forest, Coast of Main Stonington Blend, etc. I like to add a bit more aeration so either perlite, rice hulls or pumice. Alternatively you can build your own mix, but makes it easier to start with a tested recipe.
2. Chose an organic nutrient line: I went with Gaia Green because it's available, high quality and...I'm Canadian. In general, you will be top dressing and reamending your soil as you go along. You'll need a Veg and Flower product. Gaia Green has both, so can be as simple as 2 products.
3. Embrace the microbes: Find a good source of microbes and mycorrhizae. You should periodically replenish these in your grow. Just add to water.
4. Ph issues: Where organic soils tend to buffer the ph and the microbes adjust as needed, it's not as critical as hydroponics or coco medium grows. I often use distilled water as a start, and don't worry too much about it. I'll check my soil ph once in a while for sanity. I've experimented with TNB Naturals PhUp and PhDown - they work great, but not sure if needed in organic. Keep in mind that if you are using distilled water, there is no Calcium or Magnesium. I like to add a bit of oyster shell and epsom salt at the start of each grow.
5. Reamend after grow: Once you're done with a grow, you can reamend your soil. I have a large bin that I dump my soil into and add nutrients (Gaia Green + worm castings). Mix and let sit for 2 to 4 weeks to let things break down a bit.
6. Embrace the beneficials: I mostly use nematodes to keep pests in check. During a recent fungus gnat infestation I added neem meal, and this should probably be added to most soils for each grow as a preventative measure.
7. Pest management: Have a plan. Neem, essential oils, soap, etc. Lots of info on IPM measures.
8. Tea Time: I like compost teas using worm castings. I keep it simple. It's loaded with microbial life and some nutrients without being too much and causing nutrient burn. Use every 2 or 3 weeks or when it feels right.
Organic growing can be as simple or complex as you want it to be. I started simple, but my closet keeps accumulating products intended for various results. I like to re-evaluate my goals once in a while and purge as needed.
J