If your shrimp is not leftover: peel, de-vein, season lightly with salt and pepper, then saute for about 3 minutes in a little oil over medium high heat.
Put lettuces in bowl and toss to combine.
Top with other salad ingredients, and drizzle lightly with salad dressing.
I would not recommend this for brown bagging, unless you have a refrigerator at your disposal.