This mod is designed for simple installation and modification of the input.xml file. 

You will not need to make any changes to the gameplay, you can slow down the speed of your character simply by changing the value of the speed. This is not only for the speed but also for the walk and drive speed.

There are a few things to keep in mind:

If the L key does not suit you or you want to edit the speed for walking/driving, open up the file and look for:

The L key (LeftY_Axis) for walking/driving needs to be held, you do not need to press w at the same time.

The Y key (Dodge) for the base driving needs to be pressed when you are standing still.