Profile: vincew

Problem:
How to customise the datepicker used for a date field on a CRED form.

Solution:
Custom JavaScript is required.
First you need to create a JS file which is properly enqueued.
The datepicker functionality is provided by the jQuery UI datepicker library, which is initialised on dom ready.
To make sure this has already occurred, use window.onload to run the custom code.
You can set general options which apply to all datepicker instances like so:

$.datepicker.setDefaults( {
    numberOfMonths:3  // add your other 
} );

Or use the datepicker api to update options for individual instances like so:

$( '[name*="wpcf-start-date[display-only]"]' ).datepicker( "option", "numberOfMonths", 2);

Relevant Documentation:
http://api.jqueryui.com/datepicker/