If this was a real scenario it isnt unlikely that the disease it self would be so harsh that you wouldnt be able to do much. Maybe you needed a pain-meds all the time, and you would be so low on energy that you could barely make it out of bed. And because of the meds you wouldnt be able to eat, you will be bloated like no other, and swell up etc. I have seen this, and it isnt rare.
But if we say we are full of energy and spirit to the bitter end, i guess i would try to do as much as i can so my family can live without me after i go. Its hard suddenly losing the income of someone you rely on. I would like to travel, but who can afford to bring the whole familiy on a 3-month trip? Not me, and my wife cant take a 3 month break from work anyway, and the kids with a 3-month break from school wouldnt be much either. I guess everyday-life would become important. Try and make good memories for those around me, and use some extra time off work to upgrade the home or house. Try and gather thoughts on the positive. I guess it would wreck havoc on the mind to know that you can count the days you have left to live.