download phpMyAdmin latest zip from https://www.phpmyadmin.net/downloads/
extract it to ~/Code/phpmyadmin rename if required folder to easy access via valet.
copy config file using cp config.sample.inc.php config.inc.php
open config.inc.php and edit it as below
/* Authentication type */
$cfg['Servers'][$i]['auth_type'] = 'config';
/* Server parameters */
$cfg['Servers'][$i]['host'] = 'localhost';
$cfg['Servers'][$i]['compress'] = false;
$cfg['Servers'][$i]['AllowNoPassword'] = true;
$cfg['Servers'][$i]['username'] = 'root';
$cfg['Servers'][$i]['password'] = '';now got to phpmyadmin.test.