Combine salad ingredients together and toss with dressing just before seving.
I usually make up the salad and the dressing a few hours ahead of time. I just put the salad ingredients in my salad bowl and don't combine them. Put the dressing in it's own bowl and put them in the fridge, until I'm ready to serve, then I toss them together.
This salad is best eaten the same day you make it. You can eat it the next day, the lettuce is soggy though.