Look at places that hire poly students. This means that they are
very very familiar with how a poly student's timetable is like and
will most likely be very accomodating when it comes to scheduling
you. Places like The Daily Scoop, Boost, Island Creamery, Night
Safari, most of your froyo shops, have high amounts of schooling
employees.
Don't want to sugar coat it for you - but it's not going to be
slack all the way. Of course a 3.5 GPA is possible for your first
sem, but it comes with working hard, how difficult your course is,
and managing your time. If you're the kind that always needs to
study to do well, then make sure you are very disciplined with your
time. If you know you're the super slack kind, then I advise you
against a part time job lah.
I worked part time while I was in my second to final year of
poly. I started working during my holidays and it spilled over to
school. I would then ONLY work on days where I didn't have school
the next day (mostly weekends) Told them to stop scheduling me
whenever I had exams coming up/project work. I quit because I
started internship and I couldn't commit anymore. During the
semesters that I was working, my GPAs were 3.33 and 3.45. And this
was with me working my butt off if I wasn't in school.