Let's take the command Control W <. This expands the left hand window in a split window.
The only problem with this is that you must first press control w, then shift, and then ,. At least on my keyboard.
Let's remap this Control w < to Control w ,. This will save us pressing the shift key.
:nmap [press control v][press control w], [press control v][press control w]<
You can also put this in your .vimrc file for activation on startup.
Pressing control v allows you to then enter a control key in the command.
n is nmap means this only applies in normal mode.