In this guide I'm going to show you how to use Bodyslide in Fallout 4.
I recommend using it trough Vortex.
Here is a guide to show you how to install and use Vortex that I made:
https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=3492261632

It is also used in my Guide to remaster Fallout 4:
Comming soon!

We are going to need 4 to 5 files: The bodyslide program itself, a body texture (I like CBBE the most), a Bodyslide preset (Can make your own if you want, but will take a while), An outfit with bodyslide option and if the outfit doesn't come with a bodyslide build in, then you will need a patch to convert it.
For this example we will use ''Gunner Operator'' but it will work with any clothing mod that has bodyslide build in.
Go to these 4 links and download them with Vortex like you would install any other mod.
https://www.nexusmods.com/fallout4/mods/25 Bodyslide program
https://www.nexusmods.com/fallout4/mods/15 CBBE body
https://www.nexusmods.com/fallout4/mods/15734 Bodyslide preset
https://www.nexusmods.com/fallout4/mods/44863 Gunner outfit
https://www.nexusmods.com/fallout4/mods/45027 Bodyslide for Gunner

Now when all the files are installed, go to Vortex dashboard and scroll to the tools, there will be a option called ''Bodyslide'', click on the Icon to start the program.

First time use will ask you what game you want to manage, just select Fallout 4.

Now you will be presented with a big screen with plenty of slider and this might be overwhelming for you.
Don't worry it is easy when you understand what each thing does.
There are 5 important things here:
1- this is where your preset will be, if you click on this bar it will give you a drop down menu with all the presets you have saved and installed and when you click on one it will automatically adjust the sliders for you.
2- here is where an outfit goes, incase you want to adjust just one outfit/body without changing everything.
3- Batch build, this is used to apply a body preset to all outfits in the game that support bodyslide (Make sure to have ''build morphs'' check-marked).
4- Preview, it will show you the current selected outfit with the current selected preset to give you an Idea of how it would roughly look (Personally I noticed that in most cases the preview shows bigger body parts than in game, so take it with a grain of salt).
5- build just the current selected outfit with the current selected preset.

Click on our Jossie CBBE Body (Outfit) and click on batch build, it will now bring up a little pop-up asking what you want to build, just leave everything check marked and click build.
After a couple seconds it will give you a pop-up saying it is complete and now in-game when you put on the Gunner outfit, it will have the Body preset in use.
And when you take off all your clothes your body will also have the same preset on.

1- Personally I batch build everything in one go, so that all outfits are using the same body.
Then I go to outfit/body and select the CBBE body Physics, then preset switch it to a nude body, in the case of the example ''Jossie CBBE Body (Nude)'' and solo build that, it makes it look more natural in game.
2- It can happen that you might download some big mods that change the same clothes, for example Classy Chassis Outfits with the CBBE body that we used in the example clash, in that case when you batch build it will ask you which of the 2 outfits you want to use, just select the one you want and build. It won't be a problem in game.
3- Always make sure you have build morphs and the meshes\actors\characters... check-marked.

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=3498442654