How to log into admin without using a widget

There are two ways.

You can add the wp_loginout() anywhere you want on your site. See http://codex.wordpress.org/Function_Reference/wp_loginout for more info.

Another simple way is just to bookmark the wp-admin directory associated with your WordPress install. If you installed WordPress in the root directory of your site, then simply go to yourdomain.com/wp-admin and it will present a login page.

I hope this helps. If you don’t want your users to see the link, then the second option may be best.