Routine

A way to keep yourself on track with your habits is to have a routine.

Rules. Remind yourself on the current set of rules, constrains, various addictions, time-draining things. E.g. limit social media, do some stretching, …
Gratitude. Visualize and meditate on the idea that you might die today.
Long-term goals and short-term goals. Review big goals that you would like to achieve in the next years and the short term goals that lead to them that you can act on.
Visualize the day. Visualize yourself going through the day challenges and wins.

Small Actions

Small lifestyle changes that can lead to large impact:

Start every day as a producer, not a consumer.
Stretch each time you stand up.
Go for small walks after lunch.
No screens on the bedroom.
Read one page a day.
Be specific (time, words, actions).
Take time to reflect and make time for (mindfulness).
Hike often with friends.
Write more.
Consume content mindfully.
Do experiments with life (A/B tests).
Automate one thing.
Chat with everyone.
Actively reach out to friends and family.
Take notes on everything you learn and share them.
If it's under an hour, walk.
Have a day of the week where you list everything that went wrong during the weekand figure out what needs to change.

On the higher level, you can also have an Annual Review List to remind yourself some cool things!