What signs do you look for when someone is dying of lung cancer and their time is almost up?

I have a friend who is in the final stages of lung cancer. Her nursed say it is now up to God. She is not responding much to any of us. I am staying with her night and day now and I want to know what is happening as it happens. I also want to know what more I can do to make her last days easier for her, or if there is anything that can be done. It is so hard watching someone that use weigh over 230lbs, lose down to under 8olbs and she use to be so full of energy and life and now she just lays there. So if anybody knows what signs to look for and of anything that might make her more comfortable, I would really appreciate your help.. Thanks