Your metabolism is uniquely built around everything YOU think about and do. Therefore, do not copy what works for others. Thus, to start the fastest way to lose fat and not muscle is to have a thorough analysis of everything you consume so I can give you solid advice. I have a 3 step process.
1. It starts with sending me pictures of everything you consume. I calculate the macronutrients for you on a daily basis for 1 week. With your information I will teach you what, when and how much to consume in order to make you feel well fed and energized to lose fat.
2. Analyze your bodyfat amount to establish a measurable outline that puts you in a caloric deficit to use un-needed fat stores. Bodyfat checks are on a monthly basis.
3. Assess all of your overall movement per day and make adjustments that match your goals. This includes walking, cardio and resistance training to reduce fat stores.
There are countless variables dealing with age, sleep, digestion, hormones, stress, conditioning level, genetics, disease, muscle mass and more. I use my 27 years of experience, nutrition training, exercise physiology and more to weigh all of the relevant factors to make sound judgements.