check your thermo coupler..it is a little copper thinggy that allows the gas to flow to your burner.
clean your burner (rust and soot).
you press and hold the thermo coupler "button" to light
the burner, hold the button till the gas is burning under the bulb, when the gas is burning on its own relese the button, and turn the dial to the desired heat setting.
i will not sleep with the furnace running..i do not have a CO2 dector..but i am going to get one.
you really should get someone to show you how to safe/properly use your furnace....FYI, just because it is old does not mean it is not safe.
good luck..hope i did not confuse anyone??