Wiring multiple switches off 1 load wire
The basic technique is called "pigtailing".

Cut about 4-6 inches off some wire, and pull the conductors out of the outer insulation.  Do this for as many connections as you need to make. (It looks like you'll need 2 black and 2 white wires for this job.)

Strip both ends.  

For the three way, you'll wire a black stub wire to the common terminal of one three way.
Wire another to one of the terminals of the single pole.   Now, with an appropriate sized wire nut (There's usually a sizing table on the back of the package) you will wire the two stub wires together with the live wire coming into the box.  Of course, you've turned the power off and double checked the live wire with a Non contact voltage tester before touching it.  

Hopefully the three ways are already connected.  If not, you need to pull a 14-3 bundle from on switch to the other.   Connect the black and red travellers to the other screws on the three way. Pigtail the white to the white conductor to the panel.  At the other end, connect the black of a 14-2 to the common, and the other end to the fixture. White comes back from the fixture to the box, where it is wire nutted to the white of the 14-3.  And all grounds should be wired together and to the box, and to the green nut on the switch.

For the single pole, 14-2, black to the empty screw, to the fixture, and white from the fixture, and wire-nutted to the white from the panel.

If you don't have 100% confidence in your ability to do this, then hire an electrician.  This is potentially dangerous stuff.

The diagram is a bit unclear, but every wire connection MUST be made inside a box.  Don't ever nut wires together in the wall or attic.