Ok , first what version of xbtit are you use?, is you use
xBTiT v2.0.0.547 i just install it , here are the steps
go to
http://siteurls/phpmyadmin/ make sure you have a user create o put a password on root ,then creat a database , upload your php files to server ,
go to
http://siteurls/install.php follow the steps ,end at step 2 put your server detalis ..aka localhost , user of mysql, the password of user of mysql, the database name your create, . after you complete the steps delete the file
install.php & upgrade.php