In addition to all the good suggestions above, see if you can fit in a comfortable chair, and little table so your mom can have guests come over (if she would like that) so they don’t have to sit on her bed. The table is so they can have tea, or play cards, or do needlework, or whatever else they would like to do together.
Make sure that the room and house are free of tripping hazards such as rugs, and electrical cords, or excess furniture.
Would it be possible to put a CD player with headphones next to her bed? Have a variety of her favorite music, and ambient sounds available, and within reach. I’m only 55, but I don’t do music on an ipod or my phone.
Find out what scents she likes, and get some candles with those scents, or some essential oils to put a drop on a cloth, to make the room smell nice. But make sure she likes and wants extra scents in her room. Some folks get headaches from added scents, or they may be too overwhelming.
Make sure that the window treatments have the option of blackout curtains, as well as blinds or drapes that allow in dappled, or full sunlight. She may be napping during the daytime, so blackout curtains are a good idea.
Have a bell, or some other type of device, on her bedside table so that she can get your attention, if need be, without having to yell down the hall.
Also, make sure her favorite lip balm and lotion is within easy reach. Chapped lips have always been a problem for me, and I would go mad without my lip balm.
If you can set up some daily (or whatever is convenient for you, and she) to help her with her hair, and makeup if she wears it. Even cancer patients want to look their best. If she is used to getting her hair done, either schedule a regular trip to a nearby hairdresser, or see if you can find one who can come to your house.
If your mom can eat candy, keep a dish stalked with a few of her favorites.
Make sure that there is always a lidded container with a straw, filled with water, on her bedside table. She might get thirsty in the middle of the night, and the lidded bottles with straws (the insulated ones will keep the water cold) are better, so they won’t spill.
Have a pop up container of wet wipes nearby. You can get the un-scented baby wipes. They’re good for wiping sticky stuff off of fingers, or the table, or used for a cooling compress.
If your mom has a cell phone, make sure she has a charger and a cord and a plug close enough to her bed to have easy access to it.
You are doing a good deed by taking care of your Mama in your home : )
I just re-read this, Note: the candles would only be for their own scent, not for burning.