Cut the cucumbers into small cubes. Drain the excess liquid from the mushrooms. If they are large, then cut them into small pieces.
Peel the potatoes and eggs. Grate the eggs on a fine grater, cut the potatoes into small cubes. Prunes should be soft, fresh (it is not necessary to soak them beforehand). Cut the prunes as small as possible. To collect lettuce in layers:
1) potatoes + mayonnaise
2) sausage
3) mushrooms
4) cheese + mayonnaise
5) cucumbers
6) prunes + mayonnaise
7) egg