This is the practice that has made the biggest difference in making our Paleo lifestyle EASIER (for more tips like this one, check out my eBook).
I make dinner in my kitchen almost every night. And every night I pack lunches for the following day.
What this means is that I have to consciously make the effort to prepare enough food for both dinner and for lunch the next day. When dinner is done, I go ahead and put lunch-size portions in glass containers WHEN I put dinner on our plates. While we eat, the lunch portions cool.
After dinner, I do the dishes, and put the lids on our lunches. Dump some snack foods (carrots, jerky, nuts, berries, etc.) into your lunch box with them, and store in the refrigerator.
In the morning, lunch is ready to be taken to work – easy peasy.