Separate region meshing FLUENT
 

Hi
Could anyone tell me how to do a separate meshing for a particular region?
For example,
I have attached an image of flow over a square cylinder at an angle. There is different meshing for different regions as shown in the image. Can anyone give me a start on how to do this?

P.S.I have just started on ANSYS and my ANSYS Knowledge is very basic which I got from watching a couple of videos from you**be?:( Any kind of help would be appreciated/