Generating the mesh using circles and spheres

Select Mesh->Element type->Sphere. Select volume number 1 and press ESC. To see entity numbers select Label from the mouse menu or from the View menu. If you wish the geometrical entity labels to be displayed, the view mode needs to be changed to Geometry using View->Mode->Geometry (this option may also be found in the GiD Toolbar). Select Render->Normal in the mouse menu to see the labels.
Select Mesh->Element type->Circle. Select surface number 24 and press ESC.
Select Mesh->Generate mesh.
A window comes up asking whether the previous mesh should be eliminated. Click Yes.
Another window appears in which to enter the desired element size. Leave the default value unaltered and click OK. The result is a mesh as illustrated.

GiD user manual