I follow a very strict diet and eat about the same amount everyday
It's great that you have a strict diet and found something that works for you to lose weight. However it's difficult to over-emphasise just how important food and food intake is to bodybuilding success. Muscle tissue is very metabolically active. When you're trying to gain new lean tissue, you generally need to eat more quality calories and protein to 'convince' your body to start building it.
Over the duration of a cycle, you'll probably need to increase your food intake like this several times, as your body will eventually hit a new homeostasis (plateau) after each calorie increase. However, inappropriate food intake could also just as easily result in fat gain.
This is one reason it helps to have everything written down and organised, as it makes it easier to adjust and increase intake in a systematic and controlled manner from day-to-day and week-to-week, and also to develop an understanding of how your body reacts to different strategies of food/protein/fat/carb/fibre/calorie intake.
Once you start to figure this crucial diet variable out, you'll start to create the sustainable ability to build muscle tissue and to hold it post-cycle. Without this knowledge, you're possibly setting yourself up for long-term frustration, yo-yo muscle gain and loss, and ultimately a tendency to rely on escalating doses of drugs to achieve your goals.
So for now, I'd recommend you start measuring the quantities of food you eat at your meals and snacks throughout the day and writing them down. Calculate the number of grams of protein, carbs, fats and calories that are in those meals (there are lots of online calculators and reference guides).
You can then tally those numbers up and that will give you an idea of your macros - your daily intakes of protein/fats/carbs/calories. With that knowledge, you can then target how much you need to increase or alter those variables, and how to adjust the quantities/portions that you eat in your meals.
So after seeing your macros, say you decide that you want to eat 500 more calories and 50g of protein/day for the next 2 weeks. Now all you need to do is figure out what will give you that increase, and split it among your meals, or even add an additional meal to your day.
2 weeks later, you may decide on another 500 calories and 25g of protein. And so on. Without this form of organisation and structure to your dieting and knowledge of your body and how it responds, you'll find it more challenging to progress in the long-term, even on radically higher doses of steroids.