Ordering of referenced entity
If you are using Entity reference has the option to sort. I will give you three choices.

1. Manually:

Go to the /node/nodenumber/edit and you can specify the order that you want  Manually seems to be your best choice because it is your user who decides the order

2. Programatically

If want to order by descending (Ascending is the default). The only it worked for me was to use array_reverse:

$value -&gt; field_reference_field_to_reference['und']=array_reverse($value -&gt; field_reference_field_to_reference['und']);
$value -&gt; field_reference_field_to_reference['und'][]['target_id'] = $node -&gt; nid;
$value -&gt; field_reference_field_to_reference['und']=array_reverse($value -&gt; field_reference_field_to_reference['und']);
node_save($value);


3. Fields settigs in the entity reference

There is another option of sorting in your content type field settings: 

/admin/structure/types/manage/volunteer-profile/fields/field_reference 

and then you can tell it to sort by

However, to be honest the last method  number 3 has not worked for me for some reason. If you made it work. Please let me know your solution. I would love to know what am I doing wrong. :)