If I were new to the Fractal word (1st FAS gear I owned) I would quickly read the manual(s) at least one time. I say "quickly", you don't have to learn anything by heart, it's just so you have an idea what your machine can do and what you can do to/with it. When you get it in your hands your subconscious will kick in and at least you will know where to search for definitive answers. That's what I did back in 2009 when I got my Ultra and it worked just fine.
Once you have your FAS in your hands, also take a look at the front panel options (something I didn't do with my FM9 which cost me one silly question to the forum, lol), I/O etc. It will work the same way as reading the manual, you won't learn anything by heart but next time you need to do something chances are your sub will kick in and you will have an idea at least where to look or where it probably is.
While you reading the manual(s) you might want to make a small list of some initial settings you'd like to change/adjust (i.e. adjust input sensitivity, set output line levels to +4dBu or -10dBV depending on what you want to connect etc) and draw on a piece of paper what and how you want to connect to the FM9, especially if you want a complex setup. This way you won't feel overwhelmed and you won't make any mistakes that will cost you time and energy later on. Do the same thing for the switches layouts, make a few scenarios about how you want to use them and make a decision. Again, this way you won't be overwhelmed when the time comes to configure the switches (very easy and intuitive btw and that's my first FAS with switches after my old MFC101 which was not very straightforward to program).
I don't see an FM9 Edit manual (if there is one, read it too) but generally speaking it's intuitive (or maybe that's my impression as a FAS user for over 10 years, I don't know), if there isn't one just spend some time with the app just looking around so to at least you have an idea where everything is (yes, you won't know what everything does, but you will eventually, don't worry about it).
You can always take the Cooper Carter masterclass to walk you through everything...hey, I make my own presets since forever, I use only FAS since forever and I will still take the CC FM9 masterclass the moment it becomes available. Again, not mandatory.
Download all the software you are gonna need beforehand, USB drivers (if on Windows), FM9 Edit and Fractal-Bot (and FracTool if you feel like it, personally I use it only on very special occasions).
As for add-ons, that's subjective. For sure an expression pedal (with or without a switch). You don't have to buy the Mooer Shroom or any other footswitch toppers per se, I got them, they are great, I could live without them just fine. Any kind of protection you can buy and install is a good idea but not mandatory, I live in the EU so there was no way to buy some excellent covers I've found from the US (unless I wanted the customs to tear me a new one). What I did is exactly what I also did to my AF3 MK2 the moment I got it out of the box, I installed a screen protector which is nothing more or less than an iPad screen protector cut to the AF3 and FM9's screen's dimensions (can be done easily, just use the protective screen membrane the FM9 comes with as a blueprint to cut the iPad screen protector to the correct size). Cheap, easy and since it's a harder membrane it does a better job than the one it came with (which never had that purpose in the first place, to be fair). A bag or a case would be nice as well if you want to carry it with you. I went with a cheap Gator bag with the correct dimensions, light enough (user with a bad back here), does its job, don't need any more protections but that's up to you to decide what to buy.
About the IR's. Don't buy anything just yet, there is a buttload of excellent IR's installed on your machine, heck I never had to buy IR's since the AF2 era (I bought some when I had the Ultra though). First try out the countless IR's that come with your gear (record something with the looper, have it playing it over and over again and just keep selecting different IR's, write down the ones you are happy with and start using them). Then, if you feel that you need to buy some, then just buy some. Personally, I have uploaded to my AF3 and FM9 only one User IR (which nowadays I use 99% of the time) and that was free from the Axe Exchange. IR's are a big and deep rabbit whole, so tread carefully (unless you want to spend months buying and trying out IR's instead of actually playing and enjoying music).
And of course, any time you have a question just post here, this community is great, talking about infinite knowledge and experience.
That's my two cents, enjoy your FAS journey, mate!
PS1: I apologize for the "sheet"
PS2: 1000 thanks to all the members of this forum for sharing your knowledge and experience with me since 2009.
