I'm not responsible for any issues with the Steam Deck, if you do any modding on the Steam Deck it will be your own responsibility! YOU HAVE BEEN WARNED!

I got a Steam Deck now and want to make/use this guide to help others with different ways to potentially mod, customize and explain features!
I definitely won't do/get everything in this guide, but feel free to come back from time to time to see if I have something new to show.

To have a more custom experience on the Steam Deck, I recommend to use Decky:
https://decky.xyz/

To install it, go to the desktop mode on the Steam Deck.
To do this:
- Press the steam button on the left bottom of your Steam Deck.
- Go to the option Power.
- Click switch to Desktop

Now head to a browser of choice, I like Chrome and head to the website to download the Decky installer.
Then go to your file browser, download and install the program.
Now you can head back to game mode (there is a shortcut on the desktop).
When back in game mode, press the 3 dots button on the right side and scroll to the bottom.
There will be a Plugin section, in here at the top you can go the the plugin ''store'' (they are all free) and browse trough the options.
I personally use:
Animation Changer = allows you to use custom start-up video's and suspend video's (made it to use the Fallout 4 Pip-Boy startup).
Audio Loader = give sound effects when you browse around (made it make Pip-Boy sounds).
Bluetooth = make pairing a Bluetooth device faster.
CSS Loader = to customize how my Steam Deck interface looks (made it look like a Pip-Boy).
Magicblack = allows you turn the screen off while the buttons still work, nice for if you want to use the Steam Deck as a Steam controller for your PC (Steam button and 3 dot button still work).
Microsdeck = helps with micro SD-card management.
Playercount = shows how many players are playing a specific game.
Playtime = gives you an overlook on how much you played in a week/month/year and how much you played a certain game. It also adds a playtime counter to non-Steam games.
Protondb Badges = shows badges that are more accurate then the Steam badges to see if a game runs well or not on Steam Deck, also allows you to see what other users did to make a game run.
Quick Launch = to add non-Steam launchers for browsers (for example I made a link to Reddit).
Screenhotuploader = it auto uploads any in-game pictures you made to your profile (I have it set that all the pictures are private, so I can choose to or make them public or delete them).
Shotty = if I make an in-game screenshot and it gets lost or is from a non steam game, it moves it to my media folder to find it easier.
Steamgriddb = to customize the game art.

If you need the EA app or Rockstar launcher.
Or if you want to use streaming apps like Prime Video, Dinsey+ and Netflix on your steam deck.
I would recommend getting NonSteamLaunchers, just make sure that you have decky installed first and then head to this website to download the NonSteamLaunchers:
https://github.com/moraroy/NonSteamLaunchers-On-Steam-Deck

Just scroll down to the download section and start it.
Then open your file manager on the Steam Deck and install it.
Now in gaming mode, Click on the 3 dots on the right and scroll to plugins.
Form here you can use NonSteamLaunchers to download and install the different launchers.

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3526082003

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3510986759

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3519666083

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