Apologies if I’ve missed this in the thread, but a good idea is to make a book of memories.
Find photos of family, pets, houses or cars etc, print them off and stick them in a book explaining what they are. Write in the book in large clear print.
If there is a pic of two kids, Janet and John as an example, don’t write Janet and John under the pic, but put something like ‘My children, Janet born on xx xx xxxx and John born on Xx xx xxxx, Janet likes playing chess and John loved riding his bike, We used to go on holiday together to xxxxxxxx.
If there was a pic of a cat put something like ‘This is my cat fluffy’ I got him as a kitten and he lives with me at xxxxxwhatever addressxxx, he liked to sleep on the bed and I love him’.
You need to add as big a descriptor as possible, as the person with dementia may not know who or what the pics have to do with them, but pics can trigger long term memories.
If someone with dementia needs care from people outside the family then write a pen portrait for carers to read. A pen portrait can contain info such as siblings, spouse, pets, likes, dislikes, favourite music or food, plus a work/career history. The pen portrait helps the carer see the person as a real person who had a real life rather than just a shell of a person.