Note: This is the trickiest part of the project. Once you finish connecting the
LEDs you’re in the clear.
Start by cutting, and stripping completely, 2 wires about 8mm long.
Attaching the wire to the first LED is difficult. A clamp, a third hand, or a friend
(whichever is easiest to come by) would help. To get a good physical connection
on the first LED I suggest making a loop with the wire, then folding over the LED
lead (similar to how you did with the resistors). Solder.
Once you have the first one, run the wire along the rest of the LEDs, and fold
over the leads. Solder the leads to the wire.
Repeat (c) and (d) for the other set of LEDs.
I suggest you trim the folded over leads with a precise wire cutter after you
solder.
Finally, twist and solder together the ends of the wires for the two sets of LEDs.