Rather than planning a whole day's diet from scratch, it's generally more convenient to divide your calorie goal into meals, as Doris did, then prepare a variety of menus for each meal. You can decide which breakfast or what dinner far in advance, based on what you found at the supermarket, or on the spur of the moment; it's up to you. As long as all the alternatives for each meal add up to roughly the same number of calories, you can pick any menu from the list, make it up, and dig in.
As you gain experience with planning meals, you'll undoubtedly amass a larger and larger collection of different meals, all of which are interchangeable in terms of calories. Also, you'll come to learn which restaurant foods are roughly equivalent in calories to your normal allocation for each meal. As this happens, you'll probably conclude that meal planning, which originally seemed likely to endow something you once derived great joy from, eating, into an exercise with all the romance and excitement of double-entry bookkeeping, is actually liberating. No longer do you have to worry whether you're eating too much or too little. No more do you have to forego something you like because you gulped too much at lunchtime. Now you'll be able to know, in advance, how much food to make or order, eat everything you make, and enjoy it all without feeling guilty.
Weight control seems almost an extra added benefit.