The best way to do it is to load them to Fotki, Fotki re-sizes automatially.
If that is not available, somewhere in the properties of each picture are the dimensions. The best maximum dimension is 500 pixels by 500 pixels.
In your picture editing software, you should be able to change the image size, possibly somewhere in the edit menu. There should be a command to allow you to change the picture to X number of pixels by X number of pixles.
Holler if I can help more!
Thanks. I just downloaded this software today. So I’m green at it.