If you wan to enable Template path hint in your magento admin than follow this easy step. You just need to add query to your database. You also need to run this query again to disable path hint.

Go to your Database and Just run this query:

INSERT INTO core_config_data (scope, scope_id, path, value)
VALUES ('default', 0, 'dev/debug/template_hints', 1),
('default', 0, 'dev/debug/template_hints_blocks', 1);

To disable them again, run this query:
UPDATE core_config_data set value = 0 where scope = 'default' and scope_id = 0 and path ='dev/debug/template_hints'
To enable again run this query:
UPDATE core_config_data set value = 1 where scope = 'default' and scope_id = 0 and path ='dev/debug/template_hints'

You can enable Template Path Hints in your magento front as well. Follow this post if you want to enable it.