Occasionally my brain would just freeze up when I need to figure out some math and logic and just refuses to think.. and the next morning I can do within seconds... But it would've been way cooler if I could have had it done yesterday.

For me personally it helps to just do something else and leave the problem alone. I have had many times where I was stuck during the day on a particular programming problem and during my bike ride home the solution just popped in my head. It sounds a bit contradictory but try to just take a walk outside for example.

There's two things that work really well for me:

1. Rubber ducking. I usually use @levelsio for this haha. I just message him the problem. Try to describe it as well as possible. And during the process of describing it I often come up with the solution. Even before Pieter gets a chance to respond. If it's a particularly complicated issue though, it's also helpful to get another developer's perspective. – Feel free to ask such questions in the chat or ask people willing to be your rubber duck to message you.

2. For more architectural problems I tend to take a walk and just think about it. It's amazing what a 30 minute walk can do.