1. Remove Facebook/Instagram/Twitter from your phone. Using parental controls disable Safari. Remove your email too if you can.
2. Use SelfControl to block these websites for 24 hours at a time. So you only get to check these things once every day. After you've checked it, quickly block again. If 24 is too much, start with 8 or so. But always block again right after checking!
SelfControl: https://selfcontrolapp.com/
--
Few more tips:
- Pomodoro technique is nice (I built FocusList - focuslist.co) but in my experience it doesn't help if you keep thinking about how many more minutes you have to stay focused. Instead you have to forget about all that and just think about your task.
- Keep a journal of sticking with this habit. I always print current month, put it up in my kitchen and I cross off days. I'm currently doing that for my diet, but it works for any habit you wanna build.
- If you can't motivate yourself, reading a book like "Deep Work" will give you an initial push.
- Use headphones. This is individual, but speaking for me, they just gave me this feeling of immersion and it just helps me get into the zone. Get a nice pair with noise cancelling, or with those foam tips (if it's comfy), it will make you feel like you entered a different world.