Successful weight loss starts with meal planning and prepping.
A few years back I ran into a friend in the produce section of the grocery store and she showed me her detailed shopping list. As a busy working mom she said that she planned out her meals for the week then made a list of each ingredient she'd need before heading to the store. I was in awe of her organizational skills. She found the system that worked best for her family and it helped make evenings less stressful in their household.
While my friend's plan was a success for her family, it wouldn't work as well for mine. Because my kids both work a few evenings a week and my husband regularly has evening meetings, it's pretty rare that we all sit down for meals any more. What works best for us is having the makings for healthy meals available so that we can eat whenever it's convenient.
My daughter's favorite, Greek salad, is something you'll find regularly in our frig.

As I mentioned in this post Sunday afternoon is the best time for me to get meals ready for the week. If my kids aren't working or with friends they're usually quietly finishing up their homework. My husband can usually be found watching whatever game is on that afternoon. I have the kitchen to myself. I hunt through the pantry, freezer and refrigerator for whatever ingredients are left over from the week that I can prep then to make whipping up meals less time consuming later. Generally, I spend less than 90 minutes a week doing this. This week I clocked in at 1 hour and 15 minutes. Besides the salad pictured above that short time was enough to do all of the things mentioned below:
Make a huge container of hummus and chop up red peppers and cucumbers for dipping.

Saute a large bag of spinach with a small amount of olive oil and garlic.

Section two large grapefruit

-Hard boil a dozen eggs
-Clean and prep a batch of green beans that can be steamed or roasted later
-Peel and chop a cantaloupe
-Clean and chop two bunches of celery
-Slice an orange to add to a pitcher of water (the most effective way I've found to get my kids to drink more water.)
The whole wheat pita on the left (below) could be filled with the Greek salad and a little hummus for a grab-and-go meal. Ditto for a couple hard boiled eggs and some veggie sticks. The grapefruit is a family favorite to eat with any meal of the day. Hummus and veggies are a great snack as is a bowl of cantaloupe. Having the green beans prepped and the spinach ready to reheat for side dishes leaves just the preparation of an entree-something as simple as baked chicken for my meat eating family or a simple pasta dish or tofu for vegetarian me.

Not shown above is the frozen blueberries, strawberries and raspberries that my daughter loves to throw in her after-school smoothies. She uses soy or coconut milk and Greek yogurt to give it a richer taste.
This is the system that works best for our family. It might not work for a family with young children involved in weekend sports or individuals who spend their Sunday afternoon at a house of worship or with extended family. Regardless, if you can create a system and find the time to carve out for meal planning each week your chances for successful weight loss/maintenance becomes increasingly more likely.
Have you developed a meal planning system that works for you?
P.S. Prepping once a week saves time on clean up too!