How would I create custom animation?

It seems I'm on a roll with questions today...

Anyways, I've hit another wall with this one. I'm trying to create a custom walking script for my character. However, it's not the normal robloxian character, it's a custom one that I made for my game. All I need really is how would I make it so that the character can actually walk. What functions would I need?

Once again, I've already started.

local plr = game.Players.LocalPlayer
local mouse = plr:GetMouse()
local walking = false
local running = false
local jumping = false
local idle = true

for i,v in pairs(game:GetService("ControllerService"):GetChildren()) do
    v:Destroy()
end