I have question:
How to get access to /admin panel without Devise? And how to create admin user?
I am afraid your question does not make any sense. Does your application contain an admin panel? What do you mean by an admin user? Do you know how to create a normal user? Perhaps you mean that you do not know how to have users that have specific roles. If so then look at the cancan gem.
If you are new to Rails then work through some good tutorials such as railstutorial.org, which is free to use online. Then you will understand the basics of rails.
Colin
Are you using the Active Admin gem? Active Admin bundles in Devise for managing adminstrative users (which could be completely separate from whatever your application does with user registration and authorization).
Do you need to know how to get into it for the first time, so you can set up users?
Do you have a current installation using Active Admin with Devise that you cannot get into because you don't have credentials?
If you do have credentials to the application data base, you could hack the users table, but I don't really recommend doing that.
