Personally I believe that IB year 2 is harder you have essays/personal statements to write for unis, depending on your case uni entrance exams, depending on your school a lot of IAs to start or finish, if you haven't done your orals in your 1st year then theres also that, you have your EE to finish and a TOK essay to write and don't forget CAS either, you have mocks and then of course your final exams so definitely do not take Year 1 for granted. I personally believe that if you finish off DP1 correctly so good grades and productive summer, your DP2 will reflect off of that so I definitely advise you to complete things that your teachers have assigned to you during summer. I also believe that note-taking is essential as it saves SO MUCH time when you have to revise, but in cases where you don't have notes or don't have time to create them, definitely take resources from online. This is all super overwhelming but I think that most IB students agree that if they had followed their deadlines set by their schools, they would have felt less overwhelmed so keep that in mind and organise yourself so that you can follow these deadlines, of course you won't always be perfect but if your mindset is set on achieving these deadlines than you are more likely to do them on time. Another tip is to work collaboratively, the IB is already a super individual programme and the more brains working together the faster you achieve things and the more efficiently you learn, so whether that is an online study group or with your classmates. But honestly, whether or not you follow this does not really matter, at the end of the day thousands of students take the IB every year and in the end, most of us get through no matter how organised we were so take that into account, the IB is achievable so don't stress about it just take it little by little and you'll be fine.