There are a couple of ways to do this:
You could use the simple automation feature to trigger a back bet at a lower price than currently available. If you open the settings editor and pin it somewhere you could quickly update the required price trigger accordingly.
simple-back-automation.JPG
Then in the 'Automation' tab of the main application tick the back box next to the one you would like to automate.
back-automation.JPG
Or you could use the advanced automation in Guardian although this is probably a little more involved than what you want here.
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