Sorting a pivot table by value is possible following some steps, but first we'd need a data like this:

data table sorting

1. Mark the data (1), click insert (2), and then click Pivot Table (3).

ribbon insert pivot table

2. Check the label of your desire (1), then click on it, and drag it to the field of your desire (2).

check label

3. Click on any of the values (1), click data (2), and press the AZ (3). Now, press the AZ/ZA beside it (4).

ribbon data sort

4. Choose the kind of sorting you would prefer (1), and then press ok (2).

kind of sorting

Note: If there are more values, you could repeat the step 2 to 4 on all the values.