Hello! I'm currently in middle school, and this is just my personal way of studying and staying on track, but I hope it works for you too! I find bullet journalism very helpful. It decreases stress and makes planning very interesting. It's also something to consider if you're artsy or tend to doodle on the corners of your notebooks or tests. Also, you might find group studying helpful. Group studying is a bit stressful for me though, just because I don't like leading groups and that usually ends up happening. Still, consider trying it and seeing if it works for you.
Ok, so try your best to prevent cramming at all costs. The truth is, you don't need to spend that much time studying after the day you learned the information.
Go to school, take notes while you're there, come home, and review all of the information while doing a bit of research if possible. Practice the math when you get home, and write down the most simple way that you can explain how to do them. Make comparisons between today's world and the past for history (It can get you extra points on papers). Maybe try mnemonics, like PEMDAS.
Over the last Summer, I learned a lot of useful tips from some great YouTube channels. I would say, ditch the DIY channels on their study hacks. Try watching, Studytee, Studyquill, and Ruby Granger.