Hints to improve personal effectiveness

I’ve already shared how understanding work units and focusing on important problems help with efficiency.
Now I will share some techniques I use to achieve these.

How to focus on work unit?
Limit focused activity in time.
I use plain old Pomodoro timer set to 2 hours (variable thing you can change). I try to focus on 1 specific field for 2 hours ignoring all distractions.
Found something important during this interval that don’t relate to your focused activity? Skip it, it’s a distraction.
I use Toggl for time tracking but there are many alternatives.

How to focus on really important details?
Limit work unit it time.
Give yourself 1 hour to draw architectural diagram. You literally have to focus on the most important details to be on time.

What techniques do you use?