Update README

README.md

@@ -3,7 +3,12 @@
 ---
 ### Description:
 
-A simple [Minetest][] mod that can be used to remove unknown entities & nodes. Forked from [PilzAdam's ***clean*** mod][f.pilzadam].
+A [Minetest][] mod that can be used to remove/replace unknown entities, nodes, & items. Forked from [PilzAdam's ***clean*** mod][f.pilzadam].
+
+---
+### Licensing:
+
+[MIT](LICENSE.txt)
 
 ---
 ### Requirements:
@@ -12,11 +17,44 @@ A simple [Minetest][] mod that can be used to remove unknown entities & nodes. F
 - Depends: none
 
 ---
-### Licensing:
+### Usage:
 
-[MIT](LICENSE.txt)
+There are three files in the world path that can be edited: `clean_entities.json`, `clean_nodes.json`, & `clean_items.json`. If they do not already exist with the server is started they will be created automatically.
+
+They are formatted as follows:
+```json
+{
+	"remove":
+	[
+		"creatures:ghost",
+		"creatures:chicken",
+		"creatures:sheep",
+		"creatures:skeleton",
+		"creatures:zombie",
+		"creatures:oerkki",
+		"creatures:shark",
+	],
+	"replace":
+	{
+		"biofuel:biofuel":"default:leaves",
+		"helicopter:heli":"default:copper_lump",
+		"spawneggs:ghost":"alternode:key",
+		"spawneggs:oerkki":"default:mese_crystal",
+		"unifieddyes:airbrush":"default:coal_lump",
+	},
+}
+```
+
+`remove` key works for nodes & entities. `replace` key works for nodes & items. Their functions are self-explanatory.
+
+---
+### Links:
+
+- [Forum](https://forum.minetest.net/viewtopic.php?t=18381)
+- [Git repo](https://github.com/AntumMT/mod-cleaner)
+- [Changelog](changelog.txt)
+- [TODO](TODO.txt)
 
 
 [Minetest]: http://www.minetest.net/
-
 [f.pilzadam]: https://forum.minetest.net/viewtopic.php?t=2777