Forgive me for being a meathead, but how do I resize an image within a post? I've searched the forum with no luck..

I tried the whole [img=WxH] (replacing with numbers) thing, but that doesn't seem to work. Also tried switching to the graphical edit mode, which lets me drag the image to a smaller size but doesn't actually affect the settings when I save changes. I'm losing my marbles here. :cry:

Edit: I do see that we can make a thumbnail of the image by using thumb, but isn't there also a way to force images to display a certain size?