Here are video links to the mod installer guides:
Craftbukkit: https://gyazo.com/0309c1003a82e4bfd96be4cc2586e002
Forge: https://gyazo.com/a9208b1dc2bc7fcb04b05ebce4bd2079
Spigot: https://gyazo.com/80bd90994285e478de0b826a6fca15c4
Sponge Vanilla: https://gyazo.com/39a35034217b0d20ef5ba6b5b641294e