To Install:
Extract "Data" folder from 7zip file and place in [...]steamappscommonskyrim folder. Make sure you have bEnableFileSelection=1 in SkyrimPrefs.ini under [Launcher]. Make sure RealisticWaterTextures.esp and Load Loose Files is checked in Data Files in the Skyrim launcher. If you don't see RealisticWaterTextures.esp there, go into C:UsersNameAppDataLocalSkyrim, open up plugins.txt and add RealisticWaterTextures.esp under Skyrim.esm. If you are still having problems, use a mod manager to install and make sure RealisticWaterTextures.esp is checked there as well.

To Update:
Extract "Data" folder from 7zip file and place in [...]steamappscommonskyrim folder and overwrite everything.

To Uninstall delete the following:

RealisticWaterTextures.esp in the data folder.

Water:
defaultwater.dds in datatextureswater.
ocean.dds in datatextureswater.
river.dds in datatextureswater.

Foam:
fxwhitewater.dds in datatextureseffects.
fxwhitewater01.dds in datatextureseffects.
fxwhitewater02.dds in datatextureseffects.

Blacksmith's trough:
fxwatertileflat_d.dds in datatextureseffects.
fxwatertileflat_emask.dds in datatextureseffects.
fxwatertileflat_n.dds in datatextureseffects.

Waterfall:
fxwatertile01.dds in datatextureseffects.
fxwatertile01_n.dds in datatextureseffects.
fxwatertile02_n.dds in datatextureseffects.
fxfogheavy.dds in datatextureseffects.

Splashing (optional file):
fluiddrops.dds in datatextureseffects.
fluiddrops02.dds in datatextureseffects.
fluidsubsplatfilm.dds datatextureseffects.