You may or may not see mottling of the skin in the feet & lower legs and hands. The feet and hands may feel cold to the touch.
My dad had increasing episodes of apnea (absence of breathing), some lasting 30-45 seconds.
Care wise, it is imperative to turn/reposition the patient every 2 hours to prevent bedsores. The skin breaks down more easily as death nears, and although they may be inevitable, prevention of bedsores is key to keeping loved ones comfortable.
If she can't drink or swallow any longer, the little sponge-on-a-stick things (I think they are called "toothettes" here in USA) dipped in water help keep the mouth moist. Apply chap-stick frequently.
If she's still alert, ask her if there is anyone she wants to see. As death approaches, often the patients don't really want a lot of visitors and draw their "inner circle" tighter. But if someone really has something to share with her and she does not want a visit, ask them to write a message and you can read it to her.
Gosh, I wish you the best. This is probably the most difficult thing you will ever do, but it is the most loving act. God bless you for your courage and loving care.
~Suz