As little as possible.
I get the Australian govt student allowance of $230 a week, & make a point of turning up to tech as little as possible (I'm one of those annoying buggers who can get away with doing virtually no work, but always fluke the exams)
I also mow lawns & do weeding for neihbours in my street & the next street, plus I renovate bathrooms for neihbours & do painting for 'em to.
I have a unuseall payment system, they just pay me what they can afford, or what they feel like paying me, when they feel like it & I just do what I can for em when I feel like it. Consequently the neolithic couple opposited gave me $50 yesturday for mowing his front lawn last week, but a month early I mowed his front/back/side lawns & he just gave me $20.
Over the last 2 years I've ended up doing stuff for all the neihbours following the same routine. One day I was mowing the lawn of the bloke next door for $15 & some bloke from arround the corner drove past & stopped & gave me $50 on the spot to do his lawn, so I wondered arround the corner, but I did the wrong lawn, but this woman came out & gave me $20 anyway. Sometimes I'll notice someones lawn is a bit long or the weeds are taking over so I'll spent 1/2 day on it while they are at work, then a week later or something they'll drop $80 in the mailbox.
Its pretty good living in a 'old money' establishment suburb that so bloody hilly that people can't be bothered to do there own lawns, plus its really bushy almost rainforest like, here too.
One day I was taking the dog for a walk a noticed that one of the lawns I did was overgrown, so I dragged the mower out of their garage & did it on the spot. Only thing was I was barefoot & I was too lazy to walk home to put my shoes on & I cut my foot & it got infected & I ended up in hospital with cellulitis.
Also as many of the houses are getting on some have developed leaky bathrooms. They then call me down to do the job. Some are so bad the wooden studs are rotten. So I have to replace them, the put in new gyprock plasterboard, then a new shower tray & new tiles or a complete module. With jobs like that they have to fork out some money up front to cover expenses.
At the most I work 3 days a week, but its most averages out at just under 2 (a 1/2 day here, a couple hours there, etc). But this Olympics really stuff things up as everyone had relatives from overseas & whatnot coming over to stay. So they all wanted things looking beloved patriot 'n span & I ended up doing like 25 lawns in about 3 days.