OBody Guide

Learn how to switch your body preset on the fly and automatically generate random bodies for NPCs in Skyrim

Links

OStim
OBody
UIExtensions
Bodyslide and Outfit Studio

You will need a female and/or male body mod

I use CBBE 3BA for my female bodies
(Read the Body Section of my Beautification Guide if you want to know how to install this)

I also use Talos Blessed for my male bodies