I make some custom plymouths (manager splash) to Linux (UBuntu i use)->

There is the steps to install->

There is the steps for install plymouths-

Down the Plymouth, and extract, open your manager file with root privilege and
move the content of folders (plymouth) with root pivileges to /lib/plymouth/themes

then
sudo update-alternatives --install /lib/plymouth/themes/default.plymouth default.plymouth /lib/plymouth/themes/"name"plymouth/"name"plymouth 100

sudo update-alternatives --config default.plymouth
(choose your preferred)

sudo update-initramfs -u

sudo update-grub2

And the links to down the Plymouths->

Link-> Iberican

Link-> HAzard

Link->elhacker

Link-> DBZ

Link->Pirate

Link-> Women

When i can i do more Plymouths with more thems included Linux.com.

You can view the reference for this post in the blog-> Tux-a-solta

Thanks

New Plymouth with theme Linhux Foundation-> LF-PLYMOUTH

Steps to install->
[ sudo nautilus]

move the folder plymouth to /lib/plymouth/themes

[sudo update-alternatives --install /lib/plymouth/themes/default.plymouth default.plymouth /lib/plymouth/themes/portaro-plymouth/portaro.plymouth 100]

[sudo update-alternatives --config default.plymouth]

[ sudo update-initramfs -u]

[ sudo update-grub2]

To test plymouth look->

sudo plymouthd ; sudo plymouth --show-splash ; sleep 10 ; sudo plymouth --quit
Done

Visit reference on my blog-> http://tux-a-solta.blogspot.pt/2012/05/new-plymouth-theme-linux-foundation.html