LINUX,How to render words in Widget of an application to make it look more smoothly.

[cq441745656]

Give me some advice how to use method such as Anti-aliasing,Font hinting,etc.
When i run my Qt application after build it. the fonts in buttons and text widgets look totally different from previewing on Qt-creator. it's very rough.
so,please tell me a way to change it.
Any suggestion will be appreciated