Updated invocations docs

docs/contributing/INVOCATIONS.md

@@ -1,6 +1,6 @@
-# Invocations
+# Nodes
 
-Features in InvokeAI are added in the form of modular node-like systems called
+Features in InvokeAI are added in the form of modular nodes systems called
 **Invocations**.
 
 An Invocation is simply a single operation that takes in some inputs and gives
@@ -9,13 +9,35 @@ complex functionality.
 
 ## Invocations Directory
 
-InvokeAI Invocations can be found in the `invokeai/app/invocations` directory.
+InvokeAI Nodes can be found in the `invokeai/app/invocations` directory. These can be used as examples to create your own nodes.
 
-You can add your new functionality to one of the existing Invocations in this
+New nodes should be added to a subfolder in `nodes` direction found at the root level of the InvokeAI installation location. Nodes added to this folder will be able to be used upon application startup. 
-directory or create a new file in this directory as per your needs.
+
+Example `nodes`  subfolder structure:
+```py
+.
+├── __init__.py # Invoke-managed custom node loader
+│
+├── cool_node
+│   ├── __init__.py # see example below
+│   └── cool_node.py
+│
+└── my_node_pack
+    ├── __init__.py # see example below
+    ├── tasty_node.py
+    ├── bodacious_node.py
+    ├── utils.py
+    └── extra_nodes
+        └── fancy_node.py
+```
+
+Each node folder must have an `__init__.py` file that imports its nodes. Only nodes imported in the `__init__.py` file are loaded.
+ See the README in the nodes folder for more examples: 
+
+```py
+from .cool_node import CoolInvocation
+```
 
-**Note:** _All Invocations must be inside this directory for InvokeAI to
-recognize them as valid Invocations._
 
 ## Creating A New Invocation