There is no one "right" recipe for egg salad. However, most recipes for egg salad include some combination of boiled eggs, mayonnaise, mustard, and chopped celery, onion, or pickles.
Mix together eggs, mayonnaise, seasonings and optional ingredients of your choice:
1/2 c cheddar cheese, cubed and 2 Tb sour cream 1/4 c toasted almonds, sliced or chopped 1/2 c green or ripe olives, sliced 1/4 c parsley, minced; 1/4 c cucumber, minced; 3 Tb French dressing 1 c olives, sliced; 1/2 c celery, chopped; 2 Tb green onion, chopped; 1 Tb pimiento, chopped 1/4 c celery, chopped; 1/4 c pickle relish; 2 Tb green onion, finely chopped