The steps to perform the Worth It! activity:

To prepare for the session, collect any known costs relevant to the session subject. Have it collated into a structured and shareable format (like an spreadsheet)
Take 3-5 ideas or identified issues from a previous activity (or from polling the room)
Explain the goal to the room " Identify costs and the highest possible value"
Take the first idea/issue to use from the list, and put it at the head of an ant diagram ( I call it an Ant because of the 3 parts of the body, best i could do ;) )
Focus on the existing costs (it’s good to frame costs based on financial, effort or opportunity), list them in the box
Shift focus to the ROI scale box, list in the box what you think will be the most compelling return on investment (ROI)
(optional) Then using that known ROI metric, put a low point and high point on either side (low can be -10% and high point can be +10% as examples).
Now you will have the idea, the true costs you have and then the ideal ROI with the worst, best and stretch metrics.
Complete this for each idea or issue, then take a step back and have a good look at the items. Look at what each will benefit you, using the amounts of ROI as a ranking method.

Tips for running this activity

If the team can’t identify the cost, put it as an action to follow up for the team
The low and high point are optional, but a good way to present a possible worst case or stretch goal