- You're only obliged to work your contract hours. If you do more then make sure that you, personally, are getting something out of it, whether that's "I look good to my boss" or "I take job satisfaction from this" or just "I get to play with Kotlin". Consider just not working overtime.
- Take initiative, but do so sustainably. Instead of trying to look good for promo, or alternately doing the bare minimum and just scraping by, take on impactful work at a pace that won't burn you out and then leave if it isn't rewarded.
- Keep an ear to the ground. Now you've got a job, you don't need another one, but this is a business relationship just like renting a house or paying for utilities. Be aware of the job market, and consider interviewing for roles that seriously interest you. Don't go crazy and waste the time of every company in your city lest it come back to bite you, but do interview for roles you might actually take.
The last two points are fine, however.