You could use one of the login forms/buttons available in the App Store. If you don't want to offer a login possibility on the same page as the one your anonymous users can access, you could use the deep link module to create a static link to a page that is not connected to the landing page for anonymous users, but can still be accessed by those who know the link, i.e. www.google.com for regular users and www.google.com/employees for Google employees that want to login.
Dear Samet, You can manage logins indeed by going to the login.html.
1However set the the security level of your project to prototype/demo. This will allow you to manage your security on all forms.
2 Second you can make smart use of the standard metamodel for registering (system>domainmodel). No modification is needed in the META model. Set the standard Security Account_newedit to anomyous. You want anomyous users to view orders but what about registered users?
3 Create a microflow to redirect to the 'after registration form (you create it yourself)' for your registered users. Set the visibility on an object to a defined user role after registering. This can be done by the 'object properties' inspector. (on your right in the modeler) e.g. Remember to set the role on the microflow acces in your module to your allowed 'viewrole' in order to redirect registered users to another form)
I have it well explained in another topic I wrote about making a download module where anomyous users could register and then get certain downloads by giving them another role after registering.
It's explained (unfortunately without screen-shots) to registering anonymously then get download links here and might help you. I have a fully working source which I can send you or show you in a demo.