Giant-set and super-set in workouts

From your 'My Hub' page (please see below)

On the left hand side of your account, you will see the side menu where you can select 'Workouts'.

Click the workout that you would like to add a superset/giant set to.

You can then hit the group set icon.

This will allow you to pick the exercises you would like to add to a superset/giant set.

Please note, you are unable to re-arrange exercises if they are in a group/super set. To re-arrange the exercises, please remove the group/super set and make the changes, which you can then group them back together after.