How to check when character is walking?

So I've been playing some games that now have these guns made by TurboFusion. I looked at all the animations and stuff and thought "Wow! I really want to try that for my guns!" So I started looking into the scripts and I got so confused after only 220 lines. So I thought I could at least try to make the animations for walking and stuff, but I have no idea how I would do that. Is there any easy (or hard) way to do this?

EDIT: So I just read a bit of the SH Blog and found that I could do

Player.Character.Humanoid.StateChanged:connect(function(oldState, newState)
    --But I'm not sure which Enum to do for walking. I know how to for jumping, but that's it.
end)