README.md in smartsend-ruby-0.0.3 vs README.md in smartsend-ruby-0.1.0

@@ -170,5 +170,16 @@
   license: 'smartsend-license-key'
 )
 
 order.save!(account: account)
 ```
+
+### Validating account
+```ruby
+account = Smartsend::Account.new(
+  email: 'wrong-username',
+  license: 'wrong-license-key'
+)
+
+account.valid?
+  => false
+```