The first step is to select the Shire Valley Alluvial Aquifer from the aquifers layer.
2. Click the Select features using an expression button .
3. In the Select by Expression dialogue expand in the middle of the window Fields and Values and double click on AQ_NAME. This will add "AQ_NAME" to the expression on the left side of the window. Then click to add = to the expression. Now on the right side click the button and search the list that appears for Shire Valley Alluvial Aquifer. Double click on Shire Valley Alluvial Aquifer to add it to the expression, which is now:
"AQ_NAME" = 'Shire Valley Alluvial Aquifer"
4. Click to select the feature based on this expression.
5. Click Close to close the dialogue.
6. Close the attribute table.
In the map canvas you can now see the selected aquifer with a yellow boundary. Selections are yellow by default in QGIS.
Now we're going to export the Shire Valley Alluvial Aquifer.