[mkb]

what are you plugging it into? a stereo or do you have a dj mixer setup? if you don't have a stereo with a phono input, and you don't have a dj mixer, you will need a preamp of some sort. the cheapest way to get a preamp may be to buy a mixer!

to balance the tonearm, put the cartridge on and twiddle the weight until the thing balances. on the weight there is a movable ring. you want to twist that ring so that the weight stays put and the 0 on the ring lines up with the line on the post. now twiddle the weight until the recommended weight for the needle is attained.

the small metal plate with two holes in it is a headshell. that is what your cartridge attaches to