You need the Vortex mod manager:

https://github.com/Nexus-Mods/Vortex/releases

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This is a generic bug fix patch that many, many mods depend on.  If you use USSEP, you must install the VR patch too.  This is very important as starting a new game with basic USSEP will permanently break your save if you don't have the VR patch installed.  You could alternatively not install USSEP and not use any mods that require it.  That is a valid option to consider as USSEP really straddles the line between being only a bugfix patch.  However, there are mods that do require you to have USSEP.

USSEP: https://www.nexusmods.com/skyrimspecialedition/mods/266
USSEP VR Patch: https://www.nexusmods.com/skyrimspecialedition/mods/31673

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Dependencies.  These are often used as middleware like dependencies for other mods on this list.  Make sure to install all of them.

SKSE: https://skse.silverlock.org/  (get the VR version and set Vortex to launch Skyrim via the loader .exe)
XP32 Skeleton: https://www.nexusmods.com/skyrimspecialedition/mods/1988
FNIS: https://www.nexusmods.com/skyrimspecialedition/mods/3038  (download VR version and make sure to enable FNIS integration in Vortex)
JContainers SE: https://www.nexusmods.com/skyrimspecialedition/mods/16495
powerofthree's Papyrus Extender for SSE: https://www.nexusmods.com/skyrimspecialedition/mods/22854
Skyrim VR Tools: https://www.nexusmods.com/skyrimspecialedition/mods/27782

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VR specific mods.  These improve your experience with VR specifically.  VRIK gives you a first-person body and lets you equip items onto your body.  You can, for example, reach behind you and grab your bow, or unholster your sword at your belt.  Locational Damage lets you do extra damage on headshots.  Simple Realistic Archery makes you grab new arrows from your quiver.  SkyUI is a much better UI and the VR Menu Mouse Fix lets you use your controller as a virtual pointer.  Realistic Mining is just an immersion thing.

VRIK: https://www.nexusmods.com/skyrimspecialedition/mods/23416
Locational Damage SKSE VR: https://www.nexusmods.com/skyrimspecialedition/mods/26447
Simple Realistic Archery VR: https://www.nexusmods.com/skyrimspecialedition/mods/28524
SkyUI-VR: https://github.com/Odie/skyui-vr/releases
VR Menu Mouse Fix: https://www.nexusmods.com/skyrimspecialedition/mods/33414
Realistic Mining for VR: https://www.nexusmods.com/skyrimspecialedition/mods/16692

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SMIM is a mod that ups the polygon count of models.  Use the "Lite" version for VR (when you install it, you will be given the option).  I wouldn't use any other version unless you have something like a GTX 1080 Ti.  For SMIM conflicts, treat SMIM as a base; for every conflict, resolve it on SMIM as load BEFORE (except Optimized Texture, let Optimized Texture load BEFORE).

SMIM: https://www.nexusmods.com/skyrimspecialedition/mods/659

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These are texture changes.  Use Optimized Texture as a base; for every conflict, resolve it on Optimized Texture as load BEFORE.  HQ Tree Bark just makes tree textures a little higher quality.  I would recommend this instead of any flora/fauna mod (they usually kill frame rate in VR).  Majestic Mountains is the mountain mod I prefer, but there are many of them.  The HD dragon replacer is nice.  Many other texture mods exist.  Just remember that the more texture mods you install, the more GPU RAM gets eaten up.  If you install too many high resolution textures and your GPU RAM gets filled, you lose performance very fast.

Optimized Texture for SSE: https://www.nexusmods.com/skyrimspecialedition/mods/3858
HD Road Signs: https://www.nexusmods.com/skyrimspecialedition/mods/2454
RUSTIC CLOTHING: https://www.nexusmods.com/skyrimspecialedition/mods/4703
HQ Tree Bark: https://www.nexusmods.com/skyrimspecialedition/mods/6556
Majestic Mountains: https://www.nexusmods.com/skyrimspecialedition/mods/11052
Bellyaches HD Dragon Replacer Pack: https://www.nexusmods.com/skyrimspecialedition/mods/2636

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Audio enhancements.  Make sure you install the 3D positional audio patch.  It extracts into your base Skyrim VR directory, so x3daudio1_7.dll is in the same directory as SkyrimVR.exe.  Many people say to install the version from github, but many other people say that the version from github has various issues that the NexusMods version does not.  I would try the NexusMods version first.  Load Immersive Sounds AFTER Lucidity.  Audio Overhaul adds lots of crazy reverb, even with the reduced reverb patch, so you may choose to not use that one.

3D positional audio: https://www.nexusmods.com/skyrimspecialedition/mods/1897 - https://github.com/kosumosu/x3daudio1_7_hrtf/releases
Lucidity Sound FX: https://www.nexusmods.com/skyrimspecialedition/mods/1841
Immersive Sounds Compendium: https://www.nexusmods.com/skyrimspecialedition/mods/523
Audio Overhaul: https://www.nexusmods.com/skyrimspecialedition/mods/12466  (select Custom install in Vortex and make sure you apply the reduced reverb patch)

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Change the environment of the game.  Onyx VR Weather is based off Obsidian Weathers, but tweaked to better support the VR version of Skyrim.  SkyVRaan alters water quality and is specifically made for VR (other water mods use effects that only exist in Skyrim SE and may look bad in the VR version).  ETHEREAL Clouds and Cosmos are improvements, but can be considered optional.  Skyrim is Windy is also optional, but it really helps improve the feel of the environment by making all the trees and fauna sway in the wind instead of being static and unmoving.

Onyx VR Weather: https://www.nexusmods.com/skyrimspecialedition/mods/36227
SkyVRaan: https://www.nexusmods.com/skyrimspecialedition/mods/30571
ETHEREAL Clouds: https://www.nexusmods.com/skyrimspecialedition/mods/2393
ETHEREAL Cosmos: https://www.nexusmods.com/skyrimspecialedition/mods/5728
Skyrim is Windy: https://www.nexusmods.com/skyrimspecialedition/mods/5836

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This is a combat modification mod.  Mortal Enemies changes combat to make it more immersive and less video gamey.  It makes enemies commit to an attack and a direction and makes them unable to rotate through the attack to always be facing you.  It makes combat more enjoyable in VR.

Mortal Enemies SSE: https://www.nexusmods.com/skyrimspecialedition/mods/4881

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Optional improvements.  Achievements Mods Enabler let's you earn Steam achievements with mods enabled.  For body replacement mods, I would recommend Total Character Makeover.  Previous versions of my guide (and many other people) recommend WICO, but there are bugs in WICO and it is a pain to fix them.  Total Character Makeover is simple and isn't buggy and you also won't accidentally install a nude version and get yourself banned from Twitch.  Blended Roads fixes seams and stuff in roads.  It will conflict with Majestic Mountains; have Majestic Mountains load AFTER.  SSE High Quality Voices are high quality versions of all the voices in the game.  It is optional because it is like 8GB.

Achievements Mods Enabler: https://www.nexusmods.com/skyrimspecialedition/mods/245
Total Character Makeover: https://www.nexusmods.com/skyrimspecialedition/mods/1037
Blended Roads: https://www.nexusmods.com/skyrimspecialedition/mods/8834
SSE High Quality Voices: https://www.nexusmods.com/skyrimspecialedition/mods/17035

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Notes about conflicts in Vortex:

In the Mods category, if there is a conflict between mods (both change the same file), you have to resolve the mod order.  The mod that loads LAST is the one that you will see in-game.  When there is a conflict, you will see a red lightning bolt in the Dependencies column.  If you click it, you can adjust the load order rules.  Once the conflict is resolved, it turns into a green lightning bolt.

I would recommend that you consider SMIM and Optimized Textures as BASE mods.  They change a lot of models and texture and so many things conflict with them.  Go into SMIM and Optimized Textures and set them to load BEFORE every mod listed.  This will resolve a lot of the conflicts.  Next, for everything that still has issues, choose which ones load AFTER.

The only time you should use "Load before" is on your BASE mods.  For all other conflicts, use "Load after".

Usually mods will tell you in the description if there are conflicts with other mods and what their recommended resolution should be.  If they don't tell you, use your best judgement.  Choose which one you want to use and load it last.