go buy some thick white sheets (or canvas) and some black ones at walmart (cheapest) or a fabric store, Then go to the big box hardware store type place and get a couple of the cheapest work lights (walmart SOMETIMES has these for next to nothing). they're on tripods, ussually two lights per tripod, and take the metal protectors of off them (they cast odd shadows if left on). you could also get a couple hanging shop lights as long as you get the daylight flourescent bulbs for them. that way is most likely cheaper, but you'll have to figure out a way to hang them from one end on (presumably) each side of your subject. i personally have two of the work lights which have two power settings, all in all i have 2000 watts available. its about the same as a flash, except that the light doesnt stop, and its ungodly less expensive. though it does get hot. Continuous lighting. thats what its called.
those sheets are important, its what sets amatuer and professional apart. (personally, i'd be kind of offended by your friend and this temporary thing, but thats just me) just make sure you keep them clean and wrinkle free, and start figuring out what distance the subject needs to be from the sheet so that its an out of focus backdrop. some times (depending on the colour) it helps to underexpose or overexpose to compensate for the background, but thats something to try on your moms camera to really get the concept quickly.
"sex sells" is sort of the idea behind a headshot, and the only artistic license you have or should be taking is hiding any imperfections on the subjects face, and making them as attractive as possible. the lighting is typically "butterfly lighting" one light per each side of the face, it lights the face equally to eliminate any harsh shadows (and casts a soft shadow under the nose in the shape of a butterfly). hatchet lighting (light on only one side of the face) is not what your looking for, BUT..... if its all thats available, get a big piece of cardboard and cover it with tinfoil, or get one of those shades for car windshields thats bright silver. put this on the subjects unlit side to reflect a soft glowing light on that side. it wont be as bright a light as the lightsource (it shouldnt be) but its not hatchet lighting, and its ussually quite beautiful. This works best with daylight from a window as your main source of light.
it used to be recommended to get a pastel filter to put over your lens for this type of shooting (it makes everything a little fuzzy and dreamy looking) but with photoshop being able to do anything in more controlled doses, its really not that necessary. i think its better to have the original as pristine as possible before shopping it. theres quite a few things that can be done in photoshop to make a person more attractive (that is the goal) that are fairly easy. i've learned all kinds of stuff over the years (like wedding photography is NOT fun) that i'll gladly share with you whenever you'd like me too. my first advice however is to start piecing together the lighting and "backdrop" i talked about earlier. its stuff you'll be able to use later on, and it really does come in handy. i cant even count how many times its bailed me out for different assignments or projects.
not to make it sound like i want you to take out a loan, but lenses are something to consider (heavily) being as that they are what really makes the image. i'd look for a fixed 50mm 1.4 lens. its a workhorse that was the industry standard for a few decades. and in theory (and my opinion) its potentially the only lens you'll ever need. i only take it off and use something else when i absolutely have to. i was fortunate enough to find an actual nikon one for cheap. you can see god through that thing.
hell, this is a novel, i'll be on aim tonight.

--
"Alas.... Under this carnival disguise, the heart of an old youngster still beats, waiting to give it's all.."

again, thanks for the novel haha

--
If I am not for myself, who will be? If I am not for others, what am 'I'? And if not now, when?