This is not really a photography question, so move it if necessary, but it does concern posting pictures on the sight.

I have an illustration of a planned sump for my tank that I wish to display. I apparently need to shrink it to get it onto the sight, but I have no clue how to do it. When I resize the image in MS Paint, it crops it rather than resizing. I am attempting to upload it from my comp. Should I be doing it from a website instead?

Please advise.

Thanks
Richard