on the same screen as my data, click settings, bolus advice, time blocks and choose which time block/blocks you want to change, then click next, next again and on the screen you will see carbohydrate ratio and under that insulin sensitivity. The sensitivity will affect how much say 1 unit will drop your blood glucose level by.
Click done and done again and then save, be careful how much you adjust this by as a little change can have a big impack on your levels.
If you are unsure call your pump nurse and ask them for advice