Organize your syllabus
The best way to tackle the amount of work you'll need to do this semester is to first get organized. I recently came across this post on organizing your syllabus and I'm a big fan! I like being able to see everything that I need to do all in one place, and it makes it super easy to just copy down that week's to-do's in my planner. (ps - on the syllabi, the date listed will be the due date)
Once you've seen what you need to do, make goals for how to handle the bigger tasks. My own personal plan is to read daily before class, alternate weekends to either update or review my outline, and create summary review pages every month. The point of making goals isn't to just say "This is what I want to do this semester;" it's to give you something to hold you accountable and remind you to not procrastinate.
Be realistic with yourself
Again this is before you even start studying, but you need to take 5 minutes and think about your study habits in the past. Chances are, you used to study just okay and now you need to up your game and figure out how to be on top of the ball. Things to consider that might have been a weakness that you need to address: paying attention while reading instead of passively highlighting everything, retaining what you read after a few days, motivation to actually study, procrastinating.
Think back to how you study for finals and admit what was your biggest obstacle. If you start reading and think ok I need to make sure that I only highlight what's important, and as you're reading asking yourself is this important enough to highlight? then you are confronting the issue of passive reading, for example.
Experiment with different study styles
You also can consider switching up how you study. Some people prefer to get all of the studying done at once to clear up their evenings, but I personally need a mental break in the afternoons after class before I start reading in the evenings (but I am aware that if a reading takes longer than anticipated, there's a higher possibility that I'll get tired and not read as well). The other day I tried studying with my friend, and she has to listen to basically stoner music to keep her relaxed as she read. But I need absolute silence when I read or I'll get distracted, so I ended up spending 2 hours to read 10 pages.
This also brings up the point that I have to study alone. Being in a public place like a coffee shop or library will just distract me by even the slightest noise. But for other people, the temptation of watching tv or cuddling up in bed and sleeping is too high so they have to go somewhere where's there's not those temptations. I'd suggest during these first few weeks to experiment and see what helps or hurts your studying.
I'm saying this because if you sit around and wait to study for when you're super motivated, you're not going to get much done (hello, procrastination). For me, I have to plan out productive days. Since I have a 3-day weekend, I use my Fridays as my get-shit-done days. I wash dishes, do laundry, and pick up around my place while my friends are in class. Then on Friday evenings we go out and have fun. This leaves my Saturdays open for laziness. I'm not just talking about being hungover, but part of me does need a "recharge day" where I can just binge watch on Netflix. By the time Sunday rolls around, I have no excuse to not study because after a day of doing nothing I'll be in the mood to be productive, but my apartment is already clean so all that leaves left is to study. Did I put too much thought into this? Probably, but it's what works for me so that I have no choice but to get everything done that I want/need to.
Whenever it is that you sit down to study, whether it be an all out catch-up day or the day before class, make a list of everything that you need to get done. I personally like to do this in my planner and make little boxes to check off as I go. This helps make sure that after reading 20 pages for one class and 12 for another, you don't forget the 2 page handout a professor gave you as you were leaving class.
I personally don't suggest getting ahead on the readings, because it defeats the purpose. It should be that you kinda self-teach yourself an intro on a topic, and then go to class to have it better explained and burned into your memory. But if you're reading Friday's topic on subject matter jurisdiction and then going to Monday's class on personal jurisdiction, you'll have SMJ fresh on your mind and easily get it confused with PJ.
I also don't recommend that you split up your readings too much. What I mean by that is if you have 30 pages to read in contracts and 20 pages to read in property for Monday, that you don't read 15 and 10 pages of each class on Saturday and again Sunday. It would be better to read all for one class on Saturday and all for another on Sunday because you usually need to read one assigned chunk at a time to understand it.
One of the best ways that I've found to actually make myself study is to use the timer method. I'll turn my phone on Do Not Disturb and then set a timer for 25 minutes. I don't allow myself to do anything but study until that alarm goes off (including reading a text). During finals time, I'll get more strict and even pause the timer when I get up to go to the bathroom or something, just to guarantee that I'm studying for the full required time.
After my alarm goes off, I'll set a timer for 5 minutes and then I have a break. Sometimes I'll get on social media, but usually I'll let myself watch a little bit of a show during my break. No matter what, when that timer goes off I make myself go right back to studying. It's easier to finish a break knowing that I'll be back in 25 minutes to pick up where I left off. And then every few hours my break will be 30 minutes. Usually during these big breaks I try to be productive and shower or cook for myself. I've found that being rigid with myself during the study parts is the best way for me to get through my to-do list for the day.