Reducing Photo Pixel Number with Preview

[evennewerbie]

On the fun section of a forum, nearly every week I take part in a photo competition – No great pretensions but interesting to see the different interpretations that people make of any set theme.
The submitted photos have to be within a 800X600 pixel or vice versa size.
So every week I open a photo in Preview.
In a minute I compress it to the required pixel number, easy.
Every week I then spend several hours splashing about trying to get this compressed photo somewhere where I can use it, e.g. back in my original Mac photos location. Either I fail and am disqualified from the competition, or I succeed, but don't know what I did and cannot repeat the performance next time.
I cannot find comprehensible instructions on what to do after compressing the file.
Can anyone help?

 

[Lufbrarunner]

After you have scaled your image, click File > Export, you can then choose the location where you wish to save the file.
Alternatively click File > Share > Add to photos.

 

[evennewerbie]

Thank you. I believe that I had been doing those things. Maybe I should have formulated the question more precisely, have been not just what do I do but also where do I find the result of doing it?

I thought that the reducing file size action worked on the Image I applied it to, so then I was looking at the file on Photos with Info, but it was the same size as ever. Finally I worked out to look at Imports, and there was the reduced file with the same title as the original.

Possibly the writers of instructions are unable to imagine anyone to whom this would not be perfectly obvious in the first place, but there is me and also Aunt Ethel and some others I know.

 

[Lufbrarunner]

I see what ytou mean. I always rename the resized 'copy' i.e. image.jpg becomes image_small.jpg