help, i cant start my car

More info required - have you done anything on the engine since it last started OK?

Check the folling in this order;

1. Check you refitted the leads in the correct firing order,
2. Check points gap,
3. Reset ign. timing

OK, firing order is 1-2-4-3.
Turn the engine over by hand until the marker on the harmonic balancer lines up with the o deg marker in the timing cover on the firing stroke (ie both inlet and exhaust valves closed on no 1 cyl).
Remove the distributor cap and you should see the rotor pointing to where the number one lead is - this is your starting point.
Make sure lead number one is in this position, then instal each lead in the order 1-2-4-3.

Set points -
dwell should be set at 50 deg.
if you don't have a dwell meter then the gap between the contacts should be .55-.70mm,
if you dont have feeler guages then a bit of thin cardboard from a manilla folder or tally-ho pack is close enough for this exercise.

To set timing if you don't have a timing light-
Set your crank at 8-10 deg before tdc on the no1 firing stroke,
pull dizzy cap, rotor off and loosen clamp
switch key on
turn the dizzy anti clockwise till points close. then back till points just open/ small spark at points,
tighten clamp, replace rotor and cap.