Set the zigzag stitch to wider or narrower.

OR, do a double row of satinstitch to get a realy wide border.

This is or a design I downloaded from the internet and the image is already written as is. I would like the outline satin stitch a little wider but I don't know how to do it with an existing design written by someone else. I have a Brother se400 and I don't know whether there's a setting I can change there to make a wider satin stitch outline than the one programmed in the download. Can this be done somehow?

That's too bad. I have trial downloads of SewWhat and SewArt but can't figure out how to use them. Are you familiar with either of them?

Yay! I think I figured it out. I used SewWhat. Now I just have to try to run it.

I didn't realize it was an electronic design you downloaded.

For that, if you can't edit the design, you can go over the edge again with a manual satin stitch

Thank you 'lazy_gardens'. I wasn't very clear about that in my original question. I am trying a trial version of SewWhat and I was able to make the adjustment. It's called 'pull' and it can be applied to separate stitches. Wow, this machine embroidery has a vocabulary all of its own.