Let's not mess about, meal prep is simple....when you get it right.
Step 1) get a calorie target and macro split for your goal (go online, ask your coach, work it out yourself)
Step 2) put your calories/macros into myfitnesspal (go to goals > calories & macro goals and customise it)
Step 3) put in foods you LIKE, that you could eat every day for a year (within reason) and do not worry about amounts, just make 4-6 little meal EXAMPLES
Step 4) worry about the amounts! Now you have the meals in myfitnesspal, adjust the weights of foods until your daily targets are hit (potentially will have to add more meals or ingredients)
Most people make the mistake of stopping the planning here and just get cracking.
There are in fact THREE more steps!
Step 5) write your meals out in a word doc (like mine pictured below) for the full week. This means you no longer have to keep going to myfitnesspal to log foods, just look at your document, put it on your fridge and each day stay on track.