Wake up at 5:00AM.

5:15AM. Get in that ice bath. Fourty minutes or it's not worth it.

6:00AM. Write a C compiler. No help from internet.

7:15AM. Breakfast. Soylent and fifty pull-ups.

8:00AM. Enter the zone. Crush your work.

8:00PM. Exit the zone.

Just kidding, idk you kinda just have to like the problem at hand, otherwise it's too easy to go distract yourself. Distraction isn't really an evil thing though, it's not like we just enter The Zone for eight continuous hours. Engineering problems aren't usually mulled over like that, at least for me.

Oh and don't do drugs to make yourself better, that is a silly trap to fall into. Drugs are fun, do drugs! Using them as a crutch, or thinking they will alter the course of your life, that's the lie.