A useful thing to bear in mind about memory impairment: Memories aren't technically "lost" -- they're all still there within the brain. The problem lies first in saving them and then in accessing them. Working memory -- the so-called "scratch pad" where the brain stores immediate memories, like names and numbers and why you went into the next room, before they're filed permanently -- is the first part of the memory system impaired by dementia. But with help, many memories can continue to be added and accessed.
Try these tactics to reinforce working memory:
Simplify daily tasks. Streamline activities so there are fewer things to remember. This prevents the brain from wasting energy. For example, consider switching to an all-in-one shampoo/conditioner/body wash, rather than using three different products.
Use forced repetition. Do certain things the same way with intention, over and over. For example, encourage your loved one to sit in the same chair at each meal. Get him or her dressed in the same order every day (underwear, trousers, shirt, socks). Prepare the same breakfast each morning, in the same way.
Provide mental reminders. Before you go to bed, set out a toothbrush with toothpaste on it. When waking up, your loved one will have a ready visual cue to remind him to brush his teeth. It can work for you, too. The minute you decide you'll need an umbrella, for example, hang it on the doorknob rather than expecting that you'll remember to grab it on your way out.