I would recommend, keeping day as bright with plenty of light as possible and night at dark as possible. I second what the others have said. At 1 month I didn't want my DD to go for a 6-7 hour sleep without a feed as she needs food. My DD feeds a lot more at night and I think this allowed her to sleep straight through the night (from 10:30 pm till 6:30 am) but this does not occur until she was 7 weeks old. Your bub would probably be the same in no time if he is currently able to go for 6-7 hour sleep straight. He just need to get adjusted to the fact that night starts at 7 pm and not at 4 pm.
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