Sign language and brail come to mind as useful in this regard (if not for you, then for a loved one).
As for amnesia, it seems like a habit of making notes and seeking out to read your own notes would be useful. However, the trend in technology to constantly change behaviour, appearance, and functionality makes anything digital a barrier. Manual notes are also susceptible to being impossible for ageing people to make. So it's really hard to think of something.
As for amnesia, it seems like a habit of making notes and seeking out to read your own notes would be useful. However, the trend in technology to constantly change behaviour, appearance, and functionality makes anything digital a barrier. Manual notes are also susceptible to being impossible for ageing people to make. So it's really hard to think of something.