For undergraduate, first year you really need to sort out your living expenses on your own. From second and on, if your grade is good, usually CH uni will give the scholarships, not much, around 700 CHF at that time ( when i was student). Still good for a student i think.

And for 2nd and 3rd year, you can also find TA positions at Uni.

As for Masters, usually the program is quite compact, not sure that you will have time to work as partimer. but if you have to, then you can always find jobs. Its not hard to get student jobs in CH, comparing to US or Canada, at least that's how i felt years ago. Note that as student, you have the permission to work 15 hours/week ( or 20h, depends on the canton). Becausae it is legal, you wont be underpaid in general.