Ok - so even if you can't boil an egg without the egg trying to escape, this one won't phase you.
Egg salad sandwiches can be very versatile, with very little effort. Let's start with the basics.
What you need:
Mayonnaise (or Miracle Whip if you prefer)
Mustard (Senf) - depending on the variety you use it will add extra flavor
Bread - sandwich bread or rolls
These are optional - and I'm sure there are many more things you can add as well:
Nussli-salat (or any type of leafy greens)
Squeeze some mayo and spoon some mustard in. Generally, more mayo than mustard. The goal is to have enough to make the egg stick together and not crumble out of your bread, but not so much that you have a gooey mess.
Mix well. Spread on sandwich bread (or roll). Slice and enjoy.