I'm lazy and usually just use a bagged salad, then add the dressing and topping to taste. I generally don't mix everything together if I take it to a potluck or something just in case someone is allergic to nuts, but it's a lot more convenient if it's all mixed together before you leave for wherever you're going. You definitely want to have the topping and dressing prepped ahead of time because they need to cool down before you put them on the salad.
Ramen Salad Recipe
1/2 stick (1/4 cup) butter, melted
2 pkgs Ramen noodles, crushed (you only need the noodles)
1/4 C. sunflower seeds
1/2 C. slivered almonds
Heat oven to 350F. Mix ramen noodles, nuts, and butter together and spread on a cookie sheet. Stick in oven and toast until light golden brown.
1/2 C. sugar
1/4 C. vinegar (I use rice wine vinegar, but any kind works)
3/4 C. oil (I use olive, but any kind will work)
2 teaspoons soy sauce
Mix all dressing ingredients in sauce pan and simmer until sugar is melted or boil for 2 minutes. Place in fridge to cool.
You'll need around 6 cups of whatever salad you'd like to use, Just mix salad, dressing, and most of the topping together in a bowl. Sprinkle leftover topping on top before serving.