Mod is an abbreviation of the word "modification". It is a single file or multiple merged files that are installed directly in the game folder. Mods in Skyrim can be added in two ways: manually and automatically using a special program.
For automatic installation of modifications you need Nexus Mod Manager or NMM. It can be downloaded after registration on the website skyrim.nexusmods.com. Install Nexus Mod Manager on your computer.
Then open NMM. When you first run it must find the folder The Elder Scrolls V Skyrim. If the program fails to do it automatically, manually specify the path to the game. Then a window will appear asking you to enter a username and password. Enter the details you specified during registration on the website skyrim.nexusmods.com.
In running the program Nexus Mod Manager select the Mods tab. It will reflect any modifications you have installed in Skyrim. In the left pane, click the first top button and select in the dialog box, mod to install.
Also in the left pane, click on the second button from the top. Mod must be installed in the game. Launch Skyrim by double clicking on the icon to Launch Skyrim. On the next screen select "Files" and put a tick in the box next to the name of the installed mod. Start the game and check the installation result.
When you manually install you must open the archive with the mod using WinRar. Modifications in Skyrim are always installed in the Data folder. The path to the folder on the disk for a licensed game looks like this C:/Program Files/Steam/steamapps/common/skyrim/data.
All of the files contained in fashion, you need to copy into the appropriate folders of the game. Format files .esp are installed directly in the Data folder. Other files are unpacked, depending on their content. If there is a window prompting you to replace the file, click on OK.
Just a Data section contents fashion is distributed in seven folders: Meshes – three-dimensional models, Misc game sounds, Shaders– Shader files, Sounds, music, Textures – textures, Voices– voice audio sounds, Animations – animations of game characters. If you haven't installed the game, those folders in the Data partition will not. Just copy them from the installed mod. In the future you will add the files from new versions.
Open Skyrim through the Skyrim Launch. In the files section, select the new installed mod is ticked and run the game.