What I follow to stay focused on anything is very simple and practical.
Being in the field of social media at times it was really difficult to track and manage work in day to day role. So, I read somewhere about these habits long ago but never implemented them, as we all do not change something unless it starts causing big problems.
Followed two very simple habits, first writing down important things on paper and second, avoiding unnecessary hooks from online and offline.
Once I started writing down important tasks it gave me a sense of clarity and being organized. Staying away from unimportant things gave me enough time to think practically about everything and take care of myself.
I am not sure by following this thing you will be able to stay focused on anything but I can guarantee that you will improve and be at ease while doing your job, better than before.
One more bonus tip: Be specific while writing down your task as it gives more clarity and confidence to finish the job on time.
Hope this helps, Good Luck!
If you have any suggestions let me know...