Update README with structure addition instructions

README.md

@@ -43,7 +43,7 @@ Don't forget to check out the **Builder Settings** tab, where you can improve yo
 
 Construct uses Minecraft's vanilla structure system so that you can easily create and build new structures.
 
-- The simplest way to add a new structure to the structure list is to save it using a structure block. This will only save the structure to the world you're in.
+- The simplest way to add a new structure to the structure list is to save it using a structure block or the /structure command. This will only save the structure to the world you're in.
 - Importing structures from other worlds:
     1. Move the `Construct[BP]` to your `com.mojang/development_behavior_packs` folder.
     2. Drop your `.mcstructure` file in Construct's `Construct[BP]/structures` folder.