protected $customerSession;

public function __construct(
    MagentoCustomerModelSession $customerSession
){
    $this->customerSession = $customerSession;
}

// Set Value
$this->customerSession->setMyValue('test');
// Get Value
$this->customerSession->getMyValue();

$customerSession = $this->_objectManager->create('MagentoCustomerModelSessionFactory')->create(); return $customerSession->getMyValue();