TL;DR:

• Task switch frequently. Do 2 or 3 things at once if it's productive. Walk and chew gum at the same time.
• Diversify tasks and mediums. Treat them like the stocks in your retirement fund. Or the clothes in your closet, you want to be able to mix and match.
• Invest in work environments. Chairs. Monitors.
• Pay someone to do your chores.
• Retrospect. Optimize. Repeat.
• Plan for reusability. What you produce will get leveraged in different mediums by different stakeholders. Work once, use many.
• Have a vision of how products will get re-leveraged. Do the small, easy piece first. Minimum Viable Product.
• Work evenings, weekends, holidays.
• Stay healthy.
• Talk with your significant other. Develop a shared vision. Accept shared sacrifice. Enjoy shared rewards.
• If you're good at code, differentiate by working on communication and influence.

Link to How I optimised my life to make my job redundant