Periodise Your Training
If you have no structure to your training then you will hit a plateau very quickly and struggle to beat it because what you're doing is making it easy on your muscle. There needs to be a methodical plan behind your training which scientifically forces hypertrophy to happen, which requires periodization.
You move between lower volume workouts which are all about intensity, to moderate volume and then high volume etc. These are the same principles used around Y3T, which means that you're constantly manipulating your CNS and allowing yourself to continuously grow as a result. If you're doing the same volume, same reps and same level of intensity each week nothing will change.
Measure Your Food
If you're not measuring your food then you're guessing, which means you have no frigging clue what your diet really is doing. This is such a common reason for plateaus to occur simply because you are out on the required calories, whi ...