Once you have power to it, all you do is lift up the arm from the retainer, there is a rod inside the retainer pillar which operates a fairly crude lever switch under the top of the plinth.
When you lift this arm up, you should get a neon light show up in the little window on the front right. This neon illuminates the underside of the platter, which you can see because there is a mirror in view of this window. What you should see is a row of dots, which you use to get the platter to the exact speed as the flickering of the neon light acts as a strobe.
You adjust the speed via a knurled metal knob which is at the front right of the turntable.
There is a similar knurled metal knob on the front left of the turntable, this is used to change the speed from 33 to 45. Its very simply made affair, it hooks the belt to a differant pulley.
If you want to get at the belt, then look on the top metal surround faschia that goes around the platter. You will see small metal machine screws, you unfasten them and this fascia just lifts away and you can easily see the 33/45 speed change mechanism on the left and also see the belt.
If it is doing nothing, then the chances are that it will be something to do with that lever switch, or the actuator rod that runs from the arm support, it may be gummed in place, or the contacts of the switch may be tarnished.
This turntable is a very simple thing in terms of electrics, it's possible that the fine speed controller on the right hand front is broken, and you will need a fairly heavy duty rheostat to replace it, but it should not be hard to obtain something that will do the job.