Like the title says, you should either add, drop or change a letter in the previous post's word to create a new word that can be found in the English dictionary.
For example:
Post 1 - Kilt Post 2 - Kiln Post 3 - Kin Post 4 - Win Post 5 - Wine
I'm going to start with the word...
Pink
Punk
[kiss=pink_dolphin or harvest pink_dolphin]
Bun
[kiss=pink_dolphin or harvest pink_dolphin]
Gunk.
[kiss=pink_dolphin or harvest pink_dolphin]
Dank
[kiss=pink_dolphin or harvest pink_dolphin]
Prank
[kiss=pink_dolphin or harvest pink_dolphin]
Drank
[Img align=center]https://i.imgur.com/5PJRdV3.png[/img]