Plant some of every crop and keep some of every produce you make. People always want a melon at weird times and everything is a cooking ingredient.

There is no shame in looking up what people like as gifts.

Don't be scared to upgrade your tools as soon as you can because you might need them. The savings in energy and time will be worth it very very quickly.

Build a silo or two early and stock up on hay. Yes you can buy it in winter if you have to, but being prepared feels good ^^

Fishing becomes a lot easier once you get the better poles. Investing here early can be worth it. And if you hate fishing, crab pots are your friend.