As a first step you should start here with some research:-
http://www.ukba.homeoffice.gov.uk/vi...isiting/family
I suggest you follow all the links to gain as much info as possible
One of the really key issues for you will be providing evidence that you have strong and compelling reasons to return home before your visa expires.
Here is an example of the application form:-
http://www.ukba.homeoffice.gov.uk/si...isas/vaf1b.pdf
If you have any specific questions fire away. Lots of members here to help you.