diff --git a/README.md b/README.md
index 79f8889..dfdd23b 100644
--- a/README.md
+++ b/README.md
@@ -3,3 +3,12 @@ I made it because I suspected my printer's hotend thermistor was reporting too c
 
 `build.sh` generates `.3mf` files 
 with extra code to make PrusaSlicer change temperatures automatically.
+
+Defining A New Model
+======================
+
+You can add a new set of model parameters to `params.json`.
+
+Let's say you named your new parameters `my-new-parameters`.
+`build.sh my-new-parameters` will generate `my-new-parameters.3mf`,
+with PrusaSlicer temperature changes and ponies and everything.