add headings for tutorial section

Author: Andy Barrett

notebooks/SMAP/smap_as_datatree.ipynb

@@ -71,6 +71,24 @@
     "Allow 15 to 20 minutes to complete this tutorial."
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "e7eb2e5f-39e1-4bad-8fc2-65984e8527ce",
+   "metadata": {},
+   "source": [
+    "## 2. Tutorial steps"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "3b14efdc-c8d6-4831-93a3-0ab7d8f9a491",
+   "metadata": {},
+   "source": [
+    "### Import libraries\n",
+    "\n",
+    "As with all Python code, we need to import some libraries to read the data, add coordinates and plot "
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,