Remember that ‘Perfect’ is the Opposite of ‘Done’.
Your comment below is dead on. Anything is better than nothing and the more you do, the better you can refine it. What works and what doesn’t work will be somewhat individual and there’s no better test subject for what works for you than yourself.
Since there’s a relatively recent link from the Doc to that post, it’s probably safe to assume that’s the ‘best’ free stack. But more important than the ‘exact’ stack are the principles.
The general principles as outlined in that post are still the same whether you use free fields, paid fields or some combination thereof.
Step 1: Prime/Boost
Step 2: Work
Step 3: Recover (Occasionally)
With free/Patreon fields, the Priming/Boosting phase are done with:
You don’t need a Brain Pump to get amazing results. These fields work. If you go at them slowly but surely over a long time, they will still work. If you use them sporadically over an even longer time, they will still work. If you spam the tar out of them, they will still work (maybe faster than you’re prepared to deal with). The boosters make them work faster and getting a good Brain Pump will make them work much faster.
The Brain Pump is the key to getting huge results. Maybe that’s why the successor to the Superhuman Genius field is called The Brain Key…
If you’ve never experienced it before, don’t worry, you really can’t miss it at first. It will feel like your brain is literally swelling, just like a muscular pump – like your brain just did a hundred pushups. The first time I hit it, I could feel my heartbeat inside my skull.
Of course, it often becomes less noticeable the more you do it, so don’t assume a lack of sensation is also a lack of results. ‘Sensation’ is a red herring – it may or may not correlate to your outcomes. It can be ‘fun’ to experience, but it doesn’t mean these fields are or aren’t working.
Then you do the ‘Work’ with whatever wiring field you like best. Cognitive Enhancement, Enhanced Visual Processing, Brain Dancer, Synesthesia – these are all on YouTube or the cheap Patreon tier and they are still amazing.
Your Brain Pump won’t last forever – mine maxed out at around 4 hours, but your mileage may, of course, vary – so you will occasionally have to stop and ‘re-pump’.
Notably, the older free fields don’t contain any protection against overgrowth, so please be responsible and use the Autism and Brain Regeneration fields occasionally if you don’t have access to the Plasma Brain of Youth.
There are many tweaks, fiddly bits, enhancements and what-not that you can pursue or chase, but there’s no excuse to not get started immediately.
We’ll look forward to seeing you dispensing your hard won wisdom to other newcomers in a few months!
TL;DR – Brain enhancement is a marathon, not a sprint. Start now.
You’ll utilize the same principles for brain growth now (with free fields) that you will later. First Boost/Pump, then Wire. Recover occasionally.
Learning to categorize fields by ‘Booster’ and ‘Wiring’ will simplify the process of building stacks dramatically.
Experimentation is the heart of learning. Armchair esotericism (or endlessly perfecting stacks you don’t listen to!) is meaningless. Do the work. Test for results. Adjust the work plan and repeat. 
it’s all about what results you’re gunning for and you plan your stack accordingly, for general IQ increase I’m pretty sure the 2 mentioned above will help.
