How to enable php extension with `phpize`?

I tried these steps on different extensions, but I do not know why this does not work. Can't I see a change in output phpinfo()after that?

Stages:

• Uncompress php source code and change directory to ext/ext_name
• phpize
• configure
• make
• manually move the file "ext_name.so" from the directory "../.lib" to "extension_dir" specified in the file "php.ini". (or do make install)
• restart web service

Is something missing? I need to enable a specific extension in php, and there is no way to recompile the whole version of php.