Before you start you'll want to first create the render preset you're after. Adobe's support article on custom presets has a pretty comprehensive breakdown on how to do this. You can read that here.

Once you've created your preset file, put it in a location that makes sense for your project.

Inside the Review Panel navigate to the Settings screen. You'll find it by clicking the cog icon on the team page (the first screen you come to after logging in)

Once you're on the settings screen look for the option to Set a preset location for your custom render preset

In the Finder window navigate to the custom preset you created earlier and select it, then hit Save. This custom option should now be available every time you upload to Wipster using the panel.