Looking forward to watching the progress here.
My best practice suggestion is not much different than what has already been given:
Get all the debris out of the pool, leaf rake, vacuum, get as much of that out as possible meaning, not just once but keep vacuuming til you get nothing back.
Get to the pool calculator, make a bookmark for your browser and use it. I check and double check and it has served me well.
I struggled with overshooting on my applications vs my test results, mostly because I needed such major adjustments, where I would target say 50% (TA 80-120, I would target 100 and end up at 120), so I target lower and I am now landing where I wanted to be. This will take some experience for your situation.
I suggest smaller adjustments so that you are not adding and then overshooting and now correcting the other direction. That is time consuming and frustrating.
Get the CYA coming up to at least 30, this can be working while your test kit is shipped.
Get your test kit, grab a journal or excel and keep a log of your test results and pool condition and update with each test.
Get your TA inline - I target the TA first because I went through a series of bounces with my pH when my TA was 40, once I focused on TA and got it lined out then my pH snapped right inline with a small adjustment.
Get your pH to 7.2
Now you have CYA, TA & pH...
I have vinyl, so I run low calcium hardness levels, so you may want to adjust this a little bit, my impression is for vinyl this is personal preference (mine is currently 100ppm).
Start the SLAM process until you pass OCLT.
Keep brushing through SLAM, it does help.
You will have a sparkling pool at the end of this.
Last year I had a swamp and I went to perfect and never once added algaecide or floc or anything other than chlorine. Hopefully you won't have any of the pool store inspired bad habits that "most" of us show up with.
We love pictures, so feel free to post them as you are going. I took 1 pic every day around the same time to assist with my visual motivation.