Clarify what is needed to get the example working

docs/how-to-guides/block-tutorial/extending-the-query-loop-block.md

@@ -14,7 +14,7 @@ With the block variations API you can provide the default settings that make the
 
 Let's go on a journey, for example, of setting up a variation for a plugin which registers a `book` [custom post type](https://developer.wordpress.org/plugins/post-types/).
 
-### Offer sensible defaults
+### 1. Offer sensible defaults
 
 Your first step would be to create a variation which will be set up in such a way to provide a block variation which will display by default a list of books instead of blog posts. The full variation code will look something like this:
 
@@ -91,7 +91,9 @@ In this way, your block will show up just like any other block while the user is
 
 At this point, your custom variation will be virtually indistinguishable from a stand-alone block. Completely branded to your plugin, easy to discover and directly available to the user as a drop in.
 
-### Customize your variation layout
+However, your query loop variation won't work just yet — we still need to define a layout so that it can render properly.
+
+### 2. Customize your variation layout
 
 Please note that the Query Loop block supports `'block'` as a string in the `scope` property. In theory, that's to allow the variation to be picked up after inserting the block itself. Read more about the Block Variation Picker [here](https://github.com/WordPress/gutenberg/blob/HEAD/packages/block-editor/src/components/block-variation-picker/README.md).
 
@@ -125,7 +127,7 @@ In order for a variation to be connected to another Query Loop variation we need
 
 For example, if we have a Query Loop variation exposed to the inserter(`scope: ['inserter']`) with the name `products`, we can connect a scoped `block` variation by setting its `namespace` attribute to `['products']`. If the user selects this variation after having clicked `Start blank`, the namespace attribute will be overridden by the main inserter variation.
 
-### Making Gutenberg recognize your variation
+### 3. Making Gutenberg recognize your variation
 
 There is one slight problem you might have realized after implementing this variation: while it is transparent to the user as they are inserting it, Gutenberg will still recognize the variation as a Query Loop block at its core and so, after its insertion, it will show up as a Query Loop block in the tree view of the editor, for instance.