Only moving certain files automatically

I currently download all files to a desktop folder as set in Safari preferences. Once in there I want to to move only those with a certain suffix to another folder whilst leaving the others in the original download folder. Help!

Have seen several scripts doing (apparently) some of the above but not all of it. Please bear in mind you are dealing with a complete scripting novice here folks. I know enough to know I need to attach a script to a folder action (told you I was a novice!) but have no idea what the script should look like.

Any advice welcome

thanks in advance
MikeC

I think, it is better to do such task without doing your desktop HOT folder. It is better to create 1 startup item, triggered when computer starts, which does the job and terminates with prompt. Other way each time you will drag some file to process it manually, you desktop will trigger the folder action. And the desktop is a target for many services, as iCloud, and system services.

I think, such task as ordering the files on appropriate folders from such important folders need that approach. And using UTI as criteria for ordering. The movies (all types) in Movies folder, the images and photos (all types) to Pictures folder, the audio files to Music folder and so on.

Determining, that the file is one movie, the script may then check with other criteria (with size, for example) to move files to subfolders. For example, subfolder moreThan_2_gbytes_Size of folder Movies. That is, you apply multiple criteria and do all job on startup.