What do you mean by “write text and use signs”?
Memory palaces/journeys work by tricking your brain into thinking that you traveled along a route and experienced certain events along the way. You don’t need to use a physical journey though – it could be a small object like a bar of soap, a Guidonian Hand, or some of the memory spaces mentioned in The Memory Code.
I don’t have copies of De Umbris Idearum that I can send. It’s a copyrighted Kindle book. It’s only USD $7.50 for the Kindle edition.