Last time I did this guide, it was a long time ago, actually more than 2 years ago. So it's time to fix my old self and change the mistakes my dumbahh was making.

FOV. There are two types of FOV's, there is the "Viewmodel FOV" and "Screen FOV" or "Sight FOV"(SFOV).
I'll explain both in different categories. But that aside, FOV stands for Field Of View. Many people know what it is, how it works, but there are some people stuck with default settings and they always either blame their mouse or the internet or they shout at the spy for cheating since they were blind ahh hell. And don't worry, you don't need to worry about your monitor resolution, your aspect ratio and any commands/stuff to do with your PC, at all.

You may be asking, but Dr. Malpractice, why is the default bad? I'm played with it for a long tImE aND HaD nO ProBleMS!11. Shut it. Default FOV is BAD.
Both VFOV(Viewmodel FOV) and SFOV("Sight" FOV or "Screen" FOV) are bad.
They are both low and cover most of the player's screen. Now you maybe asking, again, which one means what?

VFOV is the "distance" or the "fov of your weapon model". The higher the number, the more your arms detach from your screen- Nah Nah Nah, I'm just kidding(they actually do, but I won't get deep into that). The number, for example the one I use is 80, it stays farther away from the screen and doesn't block off the screen as much. But there's one more trick up my sleeve... But I'll get to it later.
Everything summed up - VFOV makes your weapon model be farther away = blocking less of the screen.

SFOV is what I like to call "Sight(or Screen) Field of View", it's one, if not the most important thing to adjust when you freshly install your game. Increase. Your. S. F. O. V. Please, like literally this guy explained it really well!(Even though the video is as dead as my grandma)
https://www.youtube.com/watch?v=rRxFpr5Javg

Finally, the fun stuff, the stuff you actually have to input to be good at the game!(it wont make you good)
For VFOV:
viewmodel_fov x
Instead of the 'x' put a number, and I mostly recommend not going over 90 and not below 54(default) as of going further than 90 detaches your arms. and below 54 blocks your entire screen.
For SFOV(most important)
desired_fov 90
Now, you must set it to 90, as of 70 is default, and there's also a slider in advanced video settings if you manage to find it.
Tip: 90 is the maximum SFOV you can ever have and it's impossible to go over it unless you play in a Community server which has plugin that let's you do it, although if you ever see a screenshot and they have wider SFOV than normal... Well you can 100% confirm that they cheat.

Finally, the trick is here to be revealed. It's called "Minimalistic Viewmodels" and it works by bringing your weapon viewmodel DOWNN. Feels neat, nicer, and actually helps, it can also be found in the Advanced Settings.
Here's the command:
tf_use_min_viewmodels 1/0 (Enable/Disable) (it's in order, don't overthink).

And don't worry, these settings works for everyoen and everything, for all sv_pure -1,0,1,2 servers and even VALVE servers!
Comment any grammar mistakes, general mistakes I made and overall opinions on my crappy English grammar and writing skills. :)