I use PHP 5.4 and Smarty. There are two options:
Make one template for all installation pages, but assign different content, for example, on the database settings page, this will be a table with several columns "user, database name, password, port, database type", create each column by
$html->addRow($input_element_params), and then output html to the body of the template.
Make a template for each page, with all the fields inherent to them (they still will not change, only the text, since the system is multilingual), and in acc. the fields of the table just put down the variables smarty, and in the script in them already pass an array with strings in the desired language.
I do not know yet how best to do it, there is still zero experience in this, will you give me any advice? Thank.