Congrats! I just started my PhD program, so hopefully I have a little advice.
I'd say one of the most important things is to not compare yourself to other students. It was a bummer for me when everyone seemed to finish homework faster without procrastination or have all the answers in class. They were mostly faking it, but I always felt stupid. Getting past that hump early is really important!
Spend the time you think you need on your assignments and make sure you are doing something you love. There's nothing more frustrating than taking stupid classes that feel like a waste of time for you!
If you have any questions, need study tips, or anything else, please feel free to PM me
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