You'll need 14/3 from S1 to L1 to S2; 14/2 from a 15 amp circuit breaker to S1 or to L1; and 14/2 from L1 to L2 to L3 to L4.
Connect all the black wires to the black 14/2 lead, all the white wires to the white 14/2 lead and all the grounds to the ground lead.
Diagrams can be found in many Simplified Home Wiring books in your library or DIY store.

Here's your drawing. Just add more light between wired the same.
Not sure if adding a 14/2 would be code.

You haven't said where the incoming power is connected to this mess. However, as randy is aluding, you need to use the 14/3 to connect the two three way switches together (if it's cut at the lights, just wirenut it back together). Run new 14/2 from the lights to one switch. Run the power to the other switch.

Thanks, Yes the power is comming into one switch. and it looks like the easy answer is a new 14/2, from one switch to lights, and wire nutting the 14/3 back together.
Thanks Again.

There are many options.
14/2 from one switch to all lights.
14/3 from one switch to other switch.
14/2 between lights only.
14/3 from first light to last light.