Dressing Baby for the Weather

Hi there! I'm a FTM and I have a question about proper dressing of baby for the Weather. Today, for example, was 90 degrees. I dressed my 6-week old in a long sleeved onesie, socks, a hat, and a blanket over him. I kept his seat covered when we were outside the car.

But he looked so hot bundled like that, I took off the blanket. When we were in the car, I also took off his hat. But I don't know if any of that was right. We j ust got jome, and he feels so hot. He's just laying in his diaper in the crib. I hope he's cooling off or feels comfortable. I took his temp and it was in range.

Anyway, tips for dressing baby on hot days??