You do all the same things, except: (1) you can make your own choices depending on your own reasoning (e.g. you can independently decide whether circumcision/being gay is good or bad, independent of what any religion says), and (2) you’re doing things to be good, not to please god.
In fact, I consider people who are “moral” just because god says so / you fear the consequences / you want to go to heaven to actually be immoral. It’s akin to only helping in an accident if the person is rich - you’re not doing it because it’s the right thing to do, you’re just doing it to get something in return.
Edit: you can also pick any number of philosophical frameworks of morality. Personally I oscillate between golden and silver rules.