article from the blog, Yellowblissroad:
HOW TO WASH LETTUCE
I highly recommend having a salad spinner on hand for this step, but you can manage without one (the process just takes quite a bit longer).
Cut the head of lettuce up into whatever size pieces you want, removing the core as well. Next fill the bowl with water and swish the leaves around in the water to rinse the dirt away. Let the lettuce sit for a few minutes so the dirt can settle to the bottom. Lift up the colander and empty the dirty water.
Repeat this step a couple of times until the water is clean. Now you can place the top on your salad spinner and dry it.
This is a great way to get little ones to help in the kitchen! They love making the spinner spin!
HOW TO STORE LETTUCE
Place a paper towel in the bottom of a sealable container or bag. Place dried lettuce leaves in the bag on top of the paper towel. Place a second paper towel on top. Seal completely and store in your produce drawer or near the middle of your fridge.
So that’s it! Now you know how to properly store your lettuce and other leafy greens to keep them fresh for as long as possible.