So i created my test class for a controller. And I have coverage 100% but i need to make some assertions using the System.assert(), System.assertEquals(), System.assertNotEquals(), I wrote a simple assert but it's way to simple. 

@isTest 
public class ControllerTestClass 
{
   static testMethod void testMethod1() 
   {

        screen1 sc = new screen1();
        Account acc = sc.getAccount();
        acc.name = 'TestAcc';
        sc.save();
       
        System.assertEquals('TestAcc', acc.name);

          PageReference pageRef = Page.screen1VSF ;
          pageRef.getParameters().put('id',acc.Id);
          Test.setCurrentPage(pageRef);

     }
}


And the class which I'm testing.
public class screen1 
{
  
    public Account myAccount;
    public Account callAccMethod; 
    
    public Account getAccount()
    {
        if(myAccount == null)
        {
            myAccount = new account();
        }
        return myAccount;
    }

    public PageReference save()
    {
       
       callAccMethod = getAccount();
       if(callAccMethod != null)
       {
           insert myAccount;
       }
       
       PageReference pageRef = new PageReference('/apex/screen2');
       pageRef.getParameters().put('id', myAccount.Id);
       return pageRef;
       
    }
    
}