To start installing mods, you will first have to install BaseMod, which you can find here [www.nexusmods.com] (You need to have a nexus account to download it)
Make sure you have the latest version of game itself (1.0.2.13c at time of writing this)

Open the game's root folder (steam/steamapps/common/LobotomyCorp) and then into LobotomyCorp_Data.
After that drop the unarchived BaseMod in this current folder (with replacement as paste setting)
If you did everything correctly your LobotomyCorp_Data folder should look like this:
And your Managed folder like this:
Now we can get to mod installin'

Now, open the BaseMods folder in LobotomyCorp_Data.
After that open up the archive of the mod you've downloaded, transfer the contents into the BaseMods folder.
IMPORTANT: If your mod doesn't come with the dedicated folder, the archive contents will look like this:
If thats the case, make a new folder wtih any name and drop the contents inside
Now the mod should work correctly

And you should be done. Easy as.

Most mods can be found here:
Nexus Mods[www.nexusmods.com]
Wiki(RU)[lobotomycorp.fandom.com]
Korean forum[lobotomycorp.fandom.com]