Good luck with your application

There's plenty of great info here in the forum please take advantage of the resource available to optimise the application and minimise risks.
Your fiancee/wife will be the one to make the application. This will be made online. The application fee must also be made online.

Take the chance to review the Visa section of the forum, especially the various 'stickies'.
The devil really is in the detail, so try to cover all angles.