Firstly, find a time management tool first. You can consider to use Google Calendar, Microsoft Outlook, Any Calendar tool on your phone, etc.
Below is my suggestions:
1. Put in the time you need to attend classes
2. Schedule in the time for assignment and daily revision everyday after classes
3. You can find some free time slot you can use for your part time
4. Remember to ensure there is sufficient time for sleep, exercise, leisure time for meeting with friends, family gathering, etc.
5. You don't need to fill up the schedule completely. Better to keep some time for reflection and relax!
Hope this helps! Good Luck!
Might also help if you focus on one thing at a time. So when you are working, try not to think about the studying you need to do and vice versa. Build moments into your day when you can just relax. For example, at 10 pm every day (or whatever time you choose) take 10 minutes to do something fun or just to close your eyes and think about the things you enjoy most.
With every good wish.
When I was in college, I worked a part time job, which helped me reduce the amount of loans I had to take out to graduate. My path through college was not optimal, but I did learn a lot, so maybe my advice can help.
For me, I managed it by being a hermit. I mean, you know how school work goes. There are times where you have to work all weekend long due to a bad break in classes assigning difficult projects/homeworks at the same time, and there are times when there isn't that much school work in a whole week. I prioritized my work first, then school. Which meant that I never skipped a day at work or called in sick, regardless of the school work that I faced. This did mean that I didn't get the best grades, but at the time, I needed the job and I thought I could afford to get worse grades.
If I were to do it over again, I would definitely prioritize school first, then work. I didn't let myself think about it, but if I called in sick or explained to my bosses (at the time) that I needed some time to finish some hard school work, they would have understood and would have accommodated me. I really didn't want to rock the boat, so to speak, but I should have. After I graduated with a not-good GPA is when I found out how much GPA matters when you don't have internships and other experiences.
If I could advise you, I would say that the best thing you can do for your career while in college is to get an internship, try really hard, and prove to your future employer that you're smart and you can contribute. If you do that the GPA really doesn't matter too much. Then, focus on your school, and lastly your job.
This is all with the understanding that all-the-other-stuff—such as entertainment, relationships, partying, etc—is prioritized below internships, school, and work. If you do that, I really think you'll do well in your career.
Let me know if this helps and/or if there are any other questions I can answer. I wish you the best!
Hope this helps!