Develop new theme without affecting the active one

I’d say you should install WAMP or MAMP and develop locally. Then only you can see the site in progress and you don’t have to wait for files to upload to view changes. You’re just saving locally.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)